CVSS base score: 9.8 (Critical) CISA · v3.1
Score assigned by CISA's Vulnrichment program; the vendor's CVE record did not include one. Vulnrichment source record →
Vendor: Apache Software Foundation Product: Apache HTTP Server
Some mod_proxy configurations on Apache HTTP Server versions 2.4.0 through 2.4.55 allow a HTTP Request Smuggling attack. Configurations are affected when mod_proxy is enabled along with some form of RewriteRule or ProxyPassMatch in which a non-specific pattern matches some portion of the user-supplied request-target (URL) data and is then re-inserted into the proxied request-target using variable substitution. For example, something like: RewriteEngine on RewriteRule "^/here/(.*)" "http://example.com:8080/elsewhere?$1"; [P] ProxyPassReverse /here/ http://example.com:8080/ Request splitting/smuggling could result in bypass of access controls in the proxy server, proxying unintended URLs to existing origin servers, and cache poisoning. Users are recommended to update to at least version 2.4.56 of Apache HTTP Server.
No mentions found in monitored research blogs or news feeds.
| Date | Advisory | Issuer |
|---|---|---|
| 2026-01-27 | ICSA-26-027-02: Festo Didactic SE MES PC | CISA |
| 2025-05-13 | ICSA-25-133-01: Hitachi Energy Service Suite | CISA |
| 2025-04-15 | ICSA-25-105-08: ABB M2M Gateway | CISA |
| 2024-09-18 | People's Republic of China-Linked Actors Compromise Routers and IoT Devices for Botnet Operations | FBI |
| 2024-07-25 | North Korea Cyber Group Conducts Global Espionage Campaign to Advance Regime’s Military and Nuclear Programs | NSA |
| 2024-07-25 | North Korea Cyber Group Conducts Global Espionage Campaign to Advance Regime's Military and Nuclear Programs | NSA |
| 2024-02-15 | ICSA-24-046-15: Siemens SINEC NMS | CISA |
| 2024-02-15 | ICSA-24-046-11: Siemens SCALANCE XCM-/XRM-300 | CISA |
Each milestone comes from a different source, so gaps between them are gaps in what those sources publish, not evidence that nothing happened. EPSS history for this CVE holds 241 points from 2023-03-11, tracked daily from 2026-09-09; earlier points are weekly, which dates a spike to within a week. Peak probability 90.0% on 2025-03-22.
Check whether a specific version is affected →
What each source publishes about which product versions carry this vulnerability, kept as written rather than merged. Absence here means no source has published applicability data, not that nothing is affected.
Coverage across public collections only: Nuclei and OpenVAS NVT (scan);
Snort and Suricata ET Open (network); Sigma and YARA (host/SIEM);
Metasploit, Exploit-DB, public GitHub repositories and NVD exploit references (exploit). Absence
here means nothing public was found, not that detection is impossible.
GitHub PoC repositories are collected automatically by
PoC-in-GitHub (CC0) and filtered to repositories that are
still online, contain code, and are starred or at least two weeks old. They are
still not vetted: some are fakes and some are malware. Treat
them as evidence that code was published, not as code to run.
NVD exploit references are links NVD's analysts tag as exploits; they confirm
an exploit was referenced but carry no date. This product uses data from the
NVD but is not endorsed or certified by the NVD.
OpenVAS coverage derives from the Greenbone Community Feed, made available
under the Open Database License (ODbL) v1.0;
its individual Vulnerability Tests are licensed
GNU GPL v2.
| First seen | Tool | Evidence | Earliest reference |
|---|---|---|---|
| 2023-05-22 | GitHub PoC | Unvetted — public repository | dhmosfunk/CVE-2023-25690-POC +5 more |
Metasploit is dated by the first commit of the module file, Exploit-DB by its publication date, and GitHub repositories by their creation date. GitHub PoC repositories are filtered (still online, contain code, starred or at least two weeks old) but not vetted: some are fakes and some are malware, so they show that code was published, not that it works or is safe to run. Evidence tiers are explained on the About page.
Where the distribution has shipped a fix, and in which version. Green means the release has resolved it, amber that it is still open. Data from the Debian Security Tracker, used under Debian's MIT / GPLv2+ terms. Debian is upstream of several other distributions, so a fix here often precedes theirs.
| If the asset is | Remediate within | Table 1 row |
|---|---|---|
| Publicly exposed | 3 days | 5 of 16 |
| Not publicly exposed | 60 days | 13 of 16 |
BOD 26-04 replaced the single KEV deadline of BOD 22-01 with four inputs: whether the asset is publicly exposed, KEV status, whether exploitation is automatable, and technical impact. Exposure belongs to each agency's asset, not to the CVE, so both outcomes are shown. Automatable and technical impact come from the CISA assessment above. Days are calendar days; for KEV entries the clock starts on the date it was added, and otherwise when the agency identifies the vulnerability on an asset. Agencies make the final exposure call asset by asset, and may set shorter timelines.
CVE.org record → NVD entry → FortiGuard Labs → Rapid7 AttackerKB →