The GIF decoding function gdImageCreateFromGifCtx in gd_gif_in.c in the GD Graphics Library (aka libgd), as used in PHP before 5.6.31 and 7.x before 7.1.7, does not zero colorMap arrays before use. A specially crafted GIF image could use the uninitialized tables to read ~700 byte
The GIF decoding function gdImageCreateFromGifCtx in gd_gif_in.c in the GD Graphics Library (aka libgd), as used in PHP before 5.6.31 and 7.x before 7.1.7, does not zero colorMap arrays before use. A specially crafted GIF image could use the uninitialized tables to read ~700 bytes from the top of the stack, potentially disclosing sensitive information.
No structured affected-product list available — see references below for vendor advisories.
Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.
For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.
Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.
No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.