CVE-2026-52767: YesWiki Vulnerable to Unauthenticated ActivityPub Signature-Verification Bypass via `!openssl_verify(...)` accepting `int(-1)`

high Affects yeswiki/yeswiki. Feed 2026.10.29.4, updated 2026-10-29; published 2026-07-09.

YesWiki Vulnerable to Unauthenticated ActivityPub Signature-Verification Bypass via `!openssl_verify(...)` accepting `int(-1)`

Package: yeswiki/yeswiki Composer
Affected versions: >=4.6.2 and <4.6.6
Fixed in: 4.6.6
Severity: high CVSS 8.2
Exploitation: not on CISA KEV · EPSS 0% (28.8th percentile)
Published: 2026-07-09
Source: osv.dev

References

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