Every CVE Search/ Get API key

CVE-2026-77463

Remark42: Rate limit bypass via unconditional trust of X-Forwarded-For/X-Real-IP headers in direct-internet deployment

6.5 Medium

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.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
None
Integrity
Low
Availability
Low

Exploit likelihood

0.22%Unchanged since Nov 6, 2026
90%50%10%1%

What each source reports

CVE List Score used 6.5

Remark42: Rate limit bypass via unconditional trust of X-Forwarded-For/X-Real-IP headers in direct-internet deployment

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.

Record
CVE-2026-77463
CVSS 3.1
6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Weakness
CWE-348, CWE-807
Updated
2026-11-05
EUVDEUVD-2026-117799 6.5

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.

Record
EUVD-2026-117799
CVSS 3.1
6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Updated
2026-11-05
NVD 6.5

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.

Record
CVE-2026-77463
CVSS 3.1
6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Weakness
CWE-348, CWE-807
Updated
2026-11-05
OSV 6.5

Remark42: Rate limit bypass via unconditional trust of X-Forwarded-For/X-Real-IP headers in direct-internet deployment

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.

Record
CVE-2026-77463
CVSS 3.1
6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Weakness
CWE-348, CWE-807
Updated
2026-11-07

Affected products

History

History
RecordedChangedSources
aliases, referencesNVD, OSV
aliases, publishedEUVD
first indexedCVE List

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-77463 is a medium vulnerability (CVSS 6.5) in Umputun Remark42, published November 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.22%, the 12th percentile. No source names a fixed version.

References

MoveEnter Open