[HN Gopher] Hexagon fuzz: Full-system emulated fuzzing of Qualco...
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       Hexagon fuzz: Full-system emulated fuzzing of Qualcomm basebands
        
       Author : mschuster91
       Score  : 70 points
       Date   : 2025-07-02 11:00 UTC (12 hours ago)
        
 (HTM) web link (www.srlabs.de)
 (TXT) w3m dump (www.srlabs.de)
        
       | mschuster91 wrote:
       | > It powers the baseband processors found in most leading
       | smartphones, including every iPhone since generation 12 except
       | iPhone 16e and all Snapdragon-based devices.
       | 
       | Utterly unbelievable that _no_ Western government has tackled
       | that situation. The market for basebands is completely and
       | utterly _rotten_ :
       | 
       | - Qualcomm dominates the industry and can get away with pretty
       | much all sorts of behavior
       | 
       | - Samsung has their own basebands but only uses them on their
       | premium phones
       | 
       | - Huawei has basebands but IIRC they're only used in data sticks
       | and the likes, and on top of that Huawei is subject to sanctions
       | so it's even more unlikely to see them in a major phone sold in
       | Western markets.
       | 
       | - Mediatek covers the rest of the market, especially the low end.
       | 
       | That this lack of competition disincentivizes all actors from
       | making investments into code quality and security is obvious to
       | anyone who has ever looked even a bit into the _phone_ BSP side -
       | it 's hard to imagine the baseband binary blob is any different.
       | 
       | Another problem is that it's a highly difficult market to enter.
       | Pure 2G and 5G implementations exist in Osmocom, but they're
       | practically useless in a consumer environment and anything in
       | between is locked hard behind extremely complex standards on one
       | side, regulatory enforcement in the middle and finally patents.
       | Even _Apple_ hasn 't managed to kick Qualcomm and Broadcom to the
       | curb where they belong.
        
         | londons_explore wrote:
         | 4 players in the baseband market doesn't really seem too much
         | of a problem.
         | 
         | Sure - they all have different market segments - but any of
         | them would seem to have the ability to nibble into any others
         | segment if they wanted to, which in turn keeps licensing costs
         | in check.
        
           | SturgeonsLaw wrote:
           | It's just two acquisitions away from being a duopoly
        
           | mschuster91 wrote:
           | effectively it's three players given the sanctions situation
           | of Huawei and Mediatek is Taiwan based, so in the case of a
           | major war the world is down to having only Samsung and
           | Qualcomm.
        
         | londons_explore wrote:
         | I don't think the complex standards are a barrier for a team of
         | people with the capabilities of designing an ASIC. The barrier
         | is the minefield of patents. The only realistic entry into the
         | market would be to buy a lot of patents from an existing
         | player, and use them in a tit-for-tat deal for any other
         | patents one couldn't license.
        
           | mschuster91 wrote:
           | > I don't think the complex standards are a barrier for a
           | team of people with the capabilities of designing an ASIC.
           | 
           | A barrier not, but the testing effort required to achieve
           | worldwide certification, not to mention the testing effort
           | for interoperability, is enormously expensive.
           | 
           | As for the patents, Apple did just that by buying up what
           | remained of Intel's baseband business and still wasn't able
           | to deliver anything on that front in years.
        
             | walterbell wrote:
             | _> As for the patents, Apple did just that by buying up
             | what remained of Intel 's baseband business and still
             | wasn't able to deliver anything on that front in years._
             | 
             | They did eventually ship an Apple cellular modem in iPhone
             | SE, without mmWave support.
        
           | impossiblefork wrote:
           | One would think that one could have a legal ruling that
           | machine interfaces and protocols in themselves are not
           | inventions, so that anyone could follow the 5G standard, even
           | if his implementation would have to be inefficient due to not
           | being allowed to use some invention.
        
         | phh wrote:
         | > - Samsung has their own basebands but only uses them on their
         | premium phones
         | 
         | Uh? There are Samsung Exynos devices not using a Samsung
         | baseband? (Exynos spans a large size of the range, just not the
         | sub-100$)
         | 
         | > Utterly unbelievable that no Western government has tackled
         | that situation. The market for basebands is completely and
         | utterly rotten:
         | 
         | There is a global problem that in a lot of areas there is a
         | monopoly lock-in via standards. Those companies are growing
         | their strategies to control the way standards are written, to
         | make it more complicated and costly for 3rd parties to
         | implement.
         | 
         | One example of making standards more complicated which adds
         | more patents is DVB-T2 [1]. 95% of the usage of DVB-T2 compared
         | to DVB-T1 is increasing modulation rate and improving FEC, but
         | it also adds PLP (which I've seen maybe three demos of), which
         | is covered by several patents, largely increasing complexity
         | and patent cost.
         | 
         | FWIW, I love standards and I agree that the industry should
         | largely participate in making standards. I agree that standards
         | needs to have "SHALL", you can't make everything optional to
         | allow for lower costs. And I won't pretend there is an easy
         | solution to those problems.
         | 
         | Sadly, the only way I can see to improve this situation, is to
         | increase government's public funding into standardization.
         | 
         | [1] FWIW, I know nothing of how DVB-T2 has been written and who
         | did it, so it's just an example of complicated requirements
         | increasing the number of patents and thus cost of
         | implementation. It's possible that those requirements have been
         | added in good faith.
        
           | mschuster91 wrote:
           | > Uh? There are Samsung Exynos devices not using a Samsung
           | baseband?
           | 
           | The S23 for example runs a Qualcomm X70 baseband on either a
           | Samsung Exynos or Qualcomm Snapdragon depending on region.
           | Why that's the case (both using a Qualcomm modem _and_
           | different CPU vendors for the same device), no idea.
           | 
           | > Sadly, the only way I can see to improve this situation, is
           | to increase government's public funding into standardization.
           | 
           | IMHO, the thing that should be funded is the fundamental
           | research. As it is, most research in the RF and codec sector
           | is in private hands, so no wonder that things like patent
           | trolls eventually arose.
           | 
           | But eh, that's not gonna happen, not in the US (for Trumpian
           | anti-intellectualism reasons), not in Europe (we lack the
           | money, the brains and the willpower to cut through the red
           | tape) and not in China either.
        
         | surajrmal wrote:
         | If you think other players who would be competitive would have
         | better security and code quality, you're mistaken. Shipping
         | culture in hardware requires deadlines be met and that requires
         | taking shortcuts, often in software. Unless the incentive
         | structure changes all players will end up with similar results.
        
           | applied_heat wrote:
           | It's not like software outside of the hardware realm is
           | perfect either.
        
         | wyldfire wrote:
         | > Even Apple hasn't managed to kick Qualcomm and Broadcom to
         | the curb where they belong.
         | 
         | That's not quite true.
         | 
         | https://www.reuters.com/technology/apple-reveals-first-custo...
        
         | bri3d wrote:
         | You're forgetting Unisoc/Spreadtrum and ZTE in 5G, and in 4G
         | there are also a bunch of "lower-end" Chinese basebands that
         | are heavily copied from / derivative of one another.
         | 
         | > Utterly unbelievable that no Western government has tackled
         | that situation
         | 
         | Yes, I think it would behoove most countries to do what China,
         | Taiwan, and Korea have all done: force Qualcomm into antitrust
         | settlement where they have to give up parts of their patent
         | portfolio.
         | 
         | > That this lack of competition disincentivizes all actors from
         | making investments into code quality and security is obvious
         | 
         | With the above said, I don't agree with this take at all; in my
         | experience almost all hardware has horrible firmware,
         | drivers/BSP, and software no matter how competitive the market,
         | and whether it's good or not is driven almost completely by
         | company culture / standards and not by market forces. I don't
         | think the market selects for code quality at all. Janky low-
         | level code is culturally pervasive across the globe. Hardware
         | is delivered on strict fixed timeline and invisible to the end-
         | user, and there's a very strong emphasis on functional testing
         | and validation. This means that nobody cares what duct tape and
         | bailing wire hacks are necessary to get units out the door as
         | long as they pass validation, ship on time, and function. So, a
         | culture of corner-cutting hackery is passed down from
         | generation to generation of embedded engineer.
         | 
         | The only places I don't see Bad Hardware Code happen are places
         | where Software People are present and start imposing software
         | culture on the Hardware People (Google, Apple, etc.), or
         | companies making an intense, concentrated effort towards
         | becoming more Software Company oriented (Nvidia). This tends to
         | come at a major cost, too - yes, code gets better, but in
         | exchange, everything starts taking forever (see: Apple baseband
         | project).
        
       | meerasmatkhan wrote:
       | Tiktok
        
       | le-mark wrote:
       | This is a nice bit of work. Does this mean we can expect there to
       | be a lot of Qualcomm zero days incoming? Is it likely that state
       | actors have been in this already and security researchers can now
       | catch up?
        
       | spr-alex wrote:
       | Very good
        
       | jasonjayr wrote:
       | As I learn more about Radio -- is there similar fuzz testing from
       | the RF-side of these baseband processors?
       | 
       | SDR has opened my eyes up to a lot of open-to-the-world remotely
       | accessible interfaces, where the only protection is "you must
       | accept harmful interference, and you should not cause harmful
       | interference"
        
       | xvilka wrote:
       | Rizin[1] (from `dev` git) has good support of Hexagon ISA and MDT
       | images as well as RzIL uplifting, see the implementation [2].
       | Would definitely help for the static analysis in addition to
       | these tools.
       | 
       | [1] https://github.com/rizinorg/rizin
       | 
       | [2]
       | https://github.com/rizinorg/rizin/tree/dev/librz/arch/isa/he...
        
       | egberts1 wrote:
       | Some .bin images to try under Hexagon-based QEMU/Ghidra:
       | 
       | https://www.temblast.com/ref/loaders.htm
        
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       (page generated 2025-07-02 23:01 UTC)