CVE-2026-77463: umputun remark42 · Use of Less Trusted Source
Affects umputun remark42Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium : upgrade to 1.16.2 when convenient.
Data as of 5 Nov 2026, 21:04 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 6.5 |
|---|
- Patch
- Available – fixed in 1.16.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade umputun remark42 to 1.16.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| umputunremark42 | Affected
| Fixed in
|
Description
Remark42 is a self-hosted comment engine for blogs, articles, or any other place where readers can add comments. From 1.0.0 until 1.16.2, Remark42 globally trusts True-Client-IP, X-Real-IP, and X-Forwarded-For without verifying that the direct peer is a trusted proxy, and middleware.RealIP overwrites r.RemoteAddr before per-IP controls run. In a directly reachable deployment, or a proxy that forwards attacker-controlled headers, a remote attacker can rotate spoofed forwarding headers to obtain fresh token buckets for rate-limited endpoints, bypass vote de-duplication when --votes-ip is enabled, mint anonymous identities, and poison stored comment IPs and request logs. The global concurrent-request throttle and per-request timeouts still limit availability impact. Mitigation support is available in version 1.16.2, but operators must configure --trusted-proxy for the deployment topology.
References
- github.com/umputun/remark42/security/advisories/GHSA-56x6-q882-mf27 (opens in a new tab)
- github.com/umputun/remark42/pull/2116 (opens in a new tab)
- github.com/umputun/remark42/pull/2118 (opens in a new tab)
- github.com/umputun/remark42/commit/b1502801facd7782a1c70fd51f8ad5c2eb650d39 (opens in a new tab)
- github.com/umputun/remark42/commit/e62b3c830d81659cf5d2687b0c8261da7d42fdab (opens in a new tab)
- github.com/umputun/remark42/releases/tag/backend/v1.16.2 (opens in a new tab)
- remark42.com/docs/configuration/parameters/ (opens in a new tab)