CVE-2022-31778Network attack vector

Cache poisoning via retained Transfer-Encoding header

Published Aug 10, 2022 · Updated Aug 3, 2024

Improper input validation in Apache Traffic Server 8.0.0 through 9.0.2 allows remote attackers to poison its HTTP cache. The HTTP header path treats Transfer-Encoding as end-to-end metadata instead of removing this hop-by-hop field, allowing attacker-influenced framing metadata to persist in a cached response. Exploitation requires network access to a caching proxy and can corrupt responses served from that cache without granting code execution or administrative access.

CVSS severity7.5
High
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Apache Traffic Server 8.0.0 through 9.0.2 allows remote attackers to poison its HTTP cache. The HTTP header path treats Transfer-Encoding as end-to-end metadata instead of removing this hop-by-hop field, allowing attacker-influenced framing metadata to persist in a cached response. Exploitation requires network access to a caching proxy and can corrupt responses served from that cache without granting code execution or administrative access.

The record

CVE
CVE-2022-31778
Published
Aug 10, 2022
Updated
Aug 3, 2024
Vendor
The Apache Software Foundation
Product
Apache Traffic Server
Classifications
CWE-20, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 10, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.0.0 to 9.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Traffic Serverversion=8.0.0 to 9.0.2

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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