[HN Gopher] As many as 2M Cisco devices affected by actively exp...
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       As many as 2M Cisco devices affected by actively exploited 0-day
        
       Author : duxup
       Score  : 132 points
       Date   : 2025-09-25 13:22 UTC (9 hours ago)
        
 (HTM) web link (arstechnica.com)
 (TXT) w3m dump (arstechnica.com)
        
       | duxup wrote:
       | When I worked at a company that made some networking equipment
       | SNMP was a constant problem, security, bugs that crash the device
       | and so on.
       | 
       | It became clear to me over time that the pattern at that company
       | was to direct the less great engineering resources to SNMP...
        
         | hylaride wrote:
         | SNMP is one of those good ideas in theory, bad ideas in
         | practice.
         | 
         | Anyways, Cisco hasn't done great engineering pretty much since
         | the dotcom bust. They're now essentially a giant PE firm that
         | grows through acquisitions and then milks them dry. It's a
         | classic case of the accountants took over.
        
           | FuriouslyAdrift wrote:
           | Cisco's old model (which worked very well for them) was to
           | develop an outside startup and see if they gain traction
           | while keeping at least some financial/control stake to
           | democratize the risk and spend and then spin-in if it is
           | succesful (or sell off).
        
             | Our_Benefactors wrote:
             | I interviewed with Cisco once. They wanted me to do a take
             | home interview. Implement an api, make a web app, host the
             | GitHub repo somewhere, host the web app so it was publicly
             | available for them to test, make sure I included full
             | documentation and test suite. A fully tested and deployed
             | full stack application, from scratch, as a "take home
             | test". I said "no, I don't work for free".
             | 
             | That was by far the most egregious example I've encountered
             | of "we are trying to get unpaid labor from our interview
             | process."
        
               | FuriouslyAdrift wrote:
               | Yeah, that's ridiculous. It's not just FAANGs that pull
               | this crap.
        
               | lawlessone wrote:
               | FAANGS often start it and then everyone else thinks it's
               | going to make their company great if they do it too.
        
               | chuckadams wrote:
               | I think it's reasonable if one's applying as a full-stack
               | developer, the app is something like a simple TODO list
               | that isn't anything they'd actually use, and there isn't
               | a high expectation of polish. Few hours of work at most,
               | not days, and definitely not a first-interview thing.
               | Expecting you to host it yourself is definitely
               | unreasonable: they can build and run it themselves if
               | they care that much, but eyeballing the source ought to
               | be good enough in most cases.
        
               | jacquesm wrote:
               | It's only ok if they pay you for your time.
        
             | stuff4ben wrote:
             | Ah good ole MPLS (Mario, Prem, Luca, and I can't remember
             | who was S)...
        
               | lima wrote:
               | Soni
        
             | themafia wrote:
             | Sounds like something an equity or financial firm should
             | do. I'm not sure why a networking company decided to make
             | that their core competency.
        
           | MangoToupe wrote:
           | Selfishly, I'm happy and grateful they bought out chez
           | scheme, opened it up, and funded development. Do I understand
           | why? No, and I'm not going to question it!
           | 
           | EDIT: it seems like it was an acquihire of Dybvig and the
           | team working on chez for something under NDA.
        
           | rubymancer wrote:
           | Cisco employee here, this is spot on.
           | 
           | I was at a startup they acquired ~4 years ago, by now it's
           | just about milked completely dry.
           | 
           | Even though our product is close to industry-leading, they
           | laid off our product manager, then another one, the QA team,
           | and half of the devs. Unsurprisingly the product is falling
           | apart.
           | 
           | It's not a company that attempts to produce value, as with so
           | many others the product is the stock price.
           | 
           | The MBAs are showing some kind of savings on a spreadsheet
           | somewhere though, so I suppose all the sacrifices are worth
           | it.
        
             | downrightmike wrote:
             | That's what MBAs did to Intel too
        
               | neuroelectron wrote:
               | American tech sector is being destroyed so it can be
               | replaced by _____ and their surveillance state. It's
               | death by a thousand cuts, labor supply, education, taxes,
               | regulation, finance, dependencies, versioning, operating
               | systems, etc. all are being made obfuscated, complex and
               | frustrating to slow advancement and ultimately unstable
               | and impossible to maintain. Most of our tech stack
               | already has surveillance built in and that is already
               | being co-opted and we're well on our way of having it
               | outsourced to a foreign state.
        
               | iwontberude wrote:
               | and couldn't even get the stock to be worth anything
        
         | FuriouslyAdrift wrote:
         | SNMP v3 at least has some security in mind, but a lot of
         | devices are just v1 or v2c which are basically unsecured.
         | Allowing ANY write access via SNMP is a bad idea in my opinion,
         | unless you segment it out into it's own secured management or
         | out-of-band network. Even then... I'd be worried.
         | 
         | Network infrastructure security has a lot of unsolved gotchas
         | and not a lot of industry desire to fix. Most of what everyone
         | interacts with is in an abstracted or virtualized layer on top
         | of the old plumbing.
        
           | elevation wrote:
           | SNMP v2c is still common in the embedded world because it's
           | protected with a simple password so it just works out of the
           | box. SNMPv3 requires key management and an established PKI,
           | and there's no equivalent of Let's Encrypt for isolated use
           | cases in small orgs.
        
             | ay wrote:
             | SNMPv3 absolutely doesn't require PKI nor key management,
             | it works fine with shared keys.
             | 
             | You can take a look at an implementation of that, which I
             | had built for entertainment: https://github.com/ayourtch/os
             | ide/blob/main/examples/snmpwal...
        
             | mkipper wrote:
             | I never looked into the guts of how this was implemented,
             | but I worked on a product which had an SNMPv3 agent that
             | was only restricted by a username and password. I could
             | flash a PC with a fresh Ubuntu image, apt install Net-SNMP
             | and start sending SNMPv3 requests without every futzing
             | with any keys.
             | 
             | If I remember right, handling SNMPv3 _traps_ required some
             | messy key stuff so the agent still sent SNMPv2 traps, but
             | there was no requirement for keys for GET /SET.
        
       | Group_B wrote:
       | You're secure if you don't expose SNMP. Can't believe there are
       | that many devices out there with that exposed though.
        
         | FuriouslyAdrift wrote:
         | good old SNMP v1 private/private
        
         | duxup wrote:
         | It's damned if you do damned if you don't.
         | 
         | For smaller operations I think just disabling SNMP is safer due
         | to constant bugs and issues.
         | 
         | On the other hand bigger operations, you gotta monitor your
         | devices. But now you're open to the can of worms.
        
         | EvanAnderson wrote:
         | > You're secure if you don't expose SNMP.
         | 
         | Depends what you mean by "expose". Some people could read that
         | as "exposed to the Internet". I'm reading it as "exposed to
         | anything".
         | 
         | This looks like a good fun for doing lateral movement inside a
         | network. I know of lots of environments with SNMPv2 wide open
         | for "internal" networks to access.
         | 
         | Plus SNMP is UDP-based, so likely the exploit will work with a
         | one-way path and spoofed source addresses.
        
         | wil421 wrote:
         | There's no way ISPs can function without SNMP. I think network
         | management is like a 1/3 of all traffic. We process billions
         | and billions of traps daily. These are not on internet
         | connected networks and some have dedicated channels.
         | 
         | How did the attacker get the community string?
        
           | commandersaki wrote:
           | 1/3 is a absurd, more like 1/3000.
        
       | bell-cot wrote:
       | The "yet another mortal security flaw in Cisco..." stories never
       | seem to end.
       | 
       | Daydream: Journalists start ending such articles with "This is
       | the Nth critical security flaw for Cisco in just the past year.
       | Network security professionals we spoke to agree that network
       | equipment vendors X, Y, and Z all have far better track records
       | than Cisco."
        
         | fwipsy wrote:
         | The last paragraph of the article doesn't serve that purpose?
        
           | bell-cot wrote:
           | 1/4 of "yes", for this particular article. The regular
           | "brands X, Y and Z are better" part would get more traction
           | in the C-suites. And hopefully on Wall Street.
        
             | er4hn wrote:
             | Speaking (unofficially) as someone who works at one of the
             | "other brands" that reeks of journalists having a bias.
        
               | bell-cot wrote:
               | If a magazine for parents of severe-peanut-allergy
               | children ended every "may contain undisclosed peanut"
               | recall article with a "Here's our current top 3 brands
               | for child peanut safety: ...", would anyone refer to that
               | as reeking of journalistic bias?
               | 
               | How 'bout if Consumer Reports published a "We Tested 17
               | kitchen garbage disposals" article, and their 1-paragraph
               | summary of the worst-rated model said "buy one of our 3
               | top-rated models instead"?
               | 
               | (Yes, I know you're giving a "proper" response. And that
               | _very_ few journalists might say  "buy X, Y, or Z
               | instead" about a 900 lbs. gorilla like Cisco. Recall my
               | "Daydream" disclaimer.)
        
         | forinti wrote:
         | Cisco hasn't yet rolled out a version of Webex that runs on
         | Ubuntu 24.
        
           | buggeryorkshire wrote:
           | When I worked for Cisco via an acquisition every single
           | person I knew refused to use Webex in lieu of Google Meet etc
        
       | lkuty wrote:
       | I guess that `no snmp-server` is enough to be protected. Well, I
       | hope so.
        
       | morpheuskafka wrote:
       | A few years ago North Korea had some Cisco routers with all ports
       | open to the Internet, wonder if they are vulnerable.
        
         | Hikikomori wrote:
         | Sounds more like a honeypot.
        
           | ajmurmann wrote:
           | Since a single, angry dude brought down much of their
           | internet I'd not be certain
        
           | varispeed wrote:
           | Are they baiting Winnie the Pooh?
        
             | michaelcampbell wrote:
             | Isn't that China?
        
               | recursive wrote:
               | That's the reference.
        
       | nubinetwork wrote:
       | I haven't seen a large increase in snmp scanning, but I'll keep
       | watching... it's pretty low activity, usually.
        
       | happycube wrote:
       | SNMP: It's an acronym _and_ a homonym.
        
         | Noumenon72 wrote:
         | SNMP does not sound the same as any other word nor is it
         | spelled the same as some different word. I can't figure out
         | what you mean.
        
       | mleonhard wrote:
       | I think Cisco SNMP vulnerabilities have been appearing for 20
       | years or more. I wish someone would add a fuzzer to their release
       | testing script.
        
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       (page generated 2025-09-25 23:02 UTC)