Patchfirst
CVE-2022-37436 Medium · 5.3 EPSS 55.9%

Apache HTTP Server: mod_proxy prior to 2.4.55 allows a backend to trigger HTTP response splitting

Apache Software Foundation · Apache HTTP Server

Summary

The Apache HTTP Server (prior to 2.4.55) contains an HTTP response-splitting flaw in its handling of response headers from backends, where early truncation causes some headers to be emitted inside the response body. An attacker who controls a malicious backend can exploit this without authentication or user interaction over the network, and while the impact is limited to integrity, any later headers that carry security meaning will be ignored by the client.

Official description · CVE.org

Prior to Apache HTTP Server 2.4.55, a malicious backend can cause the response headers to be truncated early, resulting in some headers being incorporated into the response body. If the later headers have any security purpose, they will not be interpreted by the client.

Breakdown
28.1 / 100
Exploited
Not confirmed
Reports
1
Tactics
3/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. How attackers get in

  2. What they do

Disclosed on 17 Jan 2023. No public exploit code or confirmed exploitation is recorded.

techniques

2 , grouped by in kill-chain order, 2 cited passages 2

Initial AccessTA0001

Exploit Public-Facing Application T1190 Medium
AI mapping from the description · how it is exploited

Exploited via malicious backend affecting public-facing web server responses

a malicious backend can cause the response headers to be truncated early
From the official description (CVE.org) Original (opens in a new tab) ↗

Credential AccessTA0006

Adversary-in-the-Middle T1557 Medium also Collection
AI mapping from the description · primary impact

Response manipulation injects content altering client-side interpretation

some headers being incorporated into the response body
From the official description (CVE.org) Original (opens in a new tab) ↗

Detection

0 rules for this CVE · 159 general rules for its techniques

Rules for this CVE

0 that reference CVE-2022-37436 directly.

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What security researchers reported

Named in 1 threat report
1 reportTrustwave

Reports are matched by finding the exact id CVE-2022-37436 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.

Also mentioned in 1 community threat pulse (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

2 links, grouped by NVD tag
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