CVE-2022-31778

Transfer-Encoding not treated as hop-by-hop

7.5 HighFix available

Improper Input Validation vulnerability in handling the Transfer-Encoding header of Apache Traffic Server allows an attacker to poison the cache. This issue affects Apache Traffic Server 8.0.0 to 9.0.2.

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: High
Availability: None

Exploit likelihood

2.14%Up 1.3 points since Aug 11, 2022

What each source reports

NVD Score used 7.5

Record: CVE-2022-31778
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness: CWE-20
Updated: 2026-11-02

CVE List No score

Transfer-Encoding not treated as hop-by-hop

Record: CVE-2022-31778
Weakness: CWE-20
Updated: 2026-11-02

EUVDEUVD-2022-53171 No score

Record: EUVD-2022-53171
Updated: 2026-11-03

GitHub AdvisoriesGHSA-w7rf-qxv9-mpv7 7.5

Improper Input Validation vulnerability in handling the Transfer-Encoding header of Apache...

Record: GHSA-w7rf-qxv9-mpv7
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Weakness: CWE-20
Updated: 2026-11-02

OSVDEBIAN-CVE-2022-31778 7.5

Record: DEBIAN-CVE-2022-31778
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Updated: 2026-11-03

OSVUBUNTU-CVE-2022-31778 7.5

Record: UBUNTU-CVE-2022-31778
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Updated: 2026-11-02

OSV No score

Transfer-Encoding not treated as hop-by-hop

Record: CVE-2022-31778
Weakness: CWE-20
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`trafficserver` Debian:12	before 9.1.3+ds-1	9.1.3+ds-1
`trafficserver` Debian:10 From an advisory covering 4 CVEs	before 8.1.6+ds-1~deb10u1, plus listed versions 8.0.2+ds-18.0.2+ds-1+deb10u18.0.2+ds-1+deb10u28.0.2+ds-1+deb10u38.0.2+ds-1+deb10u4 Show 19 moreShow less 8.0.2+ds-1+deb10u58.0.2+ds-1+deb10u68.0.2+ds-1+deb10u78.0.3+ds-18.0.3+ds-28.0.3+ds-38.0.3+ds-48.0.5+ds-18.0.5+ds-28.0.5+ds-38.0.6+ds-18.0.7+ds-18.0.8+ds-18.0.8+ds-28.1.0+ds-18.1.0+ds-28.1.1+ds-18.1.1+ds-1.18.1.5+ds-1~deb11u1	8.1.6+ds-1~deb10u1
`trafficserver` Debian:11 From an advisory covering 6 CVEs	before 8.1.5+ds-1~deb11u1, plus listed versions 8.1.1+ds-1.18.1.1+ds-1.1+deb11u1	8.1.5+ds-1~deb11u1
`trafficserver` Ubuntu:16.04:LTS	All versions, plus listed versions 5.3.0-2ubuntu15.3.0-2ubuntu2	None known
`trafficserver` Ubuntu:18.04:LTS	All versions, plus listed versions 7.0.0-57.1.2+ds-27.1.2+ds-2build17.1.2+ds-3	None known
`trafficserver` Ubuntu:Pro:20.04:LTS	All versions, plus listed versions 8.0.5+ds-18.0.5+ds-28.0.5+ds-2build18.0.5+ds-2ubuntu18.0.5+ds-38.0.5+ds-3ubuntu0.1~esm1	None known
`trafficserver` Ubuntu:Pro:22.04:LTS	All versions, plus listed versions 8.1.1+ds-1.19.1.1+ds-2build19.1.1+ds-2ubuntu0.1~esm19.1.1+ds-2ubuntu0.19.1.1+ds-2ubuntu0.1+esm1	None known

History

History
Recorded	Changed	Sources
Nov 6, 2026	affected, facts	OSV
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

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

In short

CVE-2022-31778 is a high vulnerability (CVSS 7.5) in Apache Traffic Server, published August 10, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.14%, the 82nd percentile. Fixed in trafficserver 9.1.3+ds-1.