CVE-2026-102560High· 8.6▾ TwilightA flaw was found in libsoup. When the permessage-deflate WebSocket extension compresses a very large outgoing message, truncated size calculations used for GByteArray growth could wrap, causing zlib to write past the allocated buffer and…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 47.3 · likelihood 0 · exploitation 0
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A flaw was found in libsoup. When the permessage-deflate WebSocket extension compresses a very large outgoing message, truncated size calculations used for GByteArray growth could wrap, causing zlib to write past the allocated buffer and resulting in a heap buffer overflow.
libsoup3 (all versions)libsouplibsoup (all versions)libsoup (all versions)libsoup (all versions)Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
To mitigate this disable the permessage-deflate WebSocket extension if it is not required, and cap outgoing message sizes.
Connected by shared product, vendor, weakness, or advisory.
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