Answer in brief
CVE-2026-27651 records a High severity (CVSS 7.5) vulnerability in NGINX ngx_mail_auth_http_module vulnerability. The current sources do not mark it as known exploited. The current feed maps F5/NGINX Open Source (generic), F5/NGINX Plus (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-27651 records a High severity (CVSS 7.5) vulnerability in NGINX ngx_mail_auth_http_module vulnerability. The current sources do not mark it as known exploited. The current feed maps F5/NGINX Open Source (generic), F5/NGINX Plus (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps F5/NGINX Open Source (generic), F5/NGINX Plus (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| F5/NGINX Open Sourcegeneric | >=1.29.0 <1.29.7 || >=0.5.15 <1.28.3 | 1.29.7, 1.28.3 |
| F5/NGINX Plusgeneric | >=R36 <R36 P3 || >=R35 <R35 P2 || >=R34 <* || >=R33 <* || >=R32 <R32 P5 | R36 P3, R35 P2, *, R32 P5 |
Published upstream
Mar 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
When the ngx_mail_auth_http_module module is enabled on NGINX Plus or NGINX Open Source, undisclosed requests can cause worker processes to terminate. This issue may occur when (1) CRAM-MD5 or APOP authentication is enabled, and (2) the authentication server permits retry by returning the Auth-Wait response header. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps F5/NGINX Open Source (generic), F5/NGINX Plus (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| F5/NGINX Open Sourcegeneric | >=1.29.0 <1.29.7 || >=0.5.15 <1.28.3 | 1.29.7, 1.28.3 |
| F5/NGINX Plusgeneric | >=R36 <R36 P3 || >=R35 <R35 P2 || >=R34 <* || >=R33 <* || >=R32 <R32 P5 | R36 P3, R35 P2, *, R32 P5 |
Published upstream
Mar 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 15, 2026
When the ngx_mail_auth_http_module module is enabled on NGINX Plus or NGINX Open Source, undisclosed requests can cause worker processes to terminate. This issue may occur when (1) CRAM-MD5 or APOP authentication is enabled, and (2) the authentication server permits retry by returning the Auth-Wait response header. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Quoted source text, attributed separately from HOL analysis.