CVE-2024-31852: LLVM before 18.1.3 generates code in which the LR register can be overwritten without data being saved to the stack, and thus there can sometimes be an exploita

LLVM before 18.1.3 generates code in which the LR register can be overwritten without data being saved to the stack, and thus there can sometimes be an exploita

LLVM before 18.1.3 generates code in which the LR register can be overwritten without data being saved to the stack, and thus there can sometimes be an exploitable error in the flow of control. This affects the ARM backend and can be demonstrated with Clang. NOTE: the vendor perspective is "we don't have strong objections for a CVE to be created ... It does seem that the likelihood of this miscompile enabling an exploit remains very low, because the miscompile resulting in this JOP gadget is such that the function is most likely to crash on most valid inputs to the function. So, if this function is covered by any testing, the miscompile is most likely to be discovered before the binary is shipped to production."

Description from the National Vulnerability Database, published by MITRE

What it means for a small business

If your business uses this software, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.99%, higher than 62% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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