View at Official debian advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2023-1999 not yet assigned priority: Debian including 4 source packages (firefox, firefox-esr, libwebp, thunderbird), 16 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 16.
There exists a use after free/double free in libwebp. An attacker can use the ApplyFiltersAndEncode() function and loop through to free best.bw and assign best = trial pointer. The second loop will then return 0 because of an Out of memory error in VP8 encoder, the pointer is still assigned to trial and the AddressSanitizer will attempt a double free.