CVE-2021-23339 json
HTTP Request Smuggling
published 2021-02-17 5 y ago modified 2026-07-08 4 mo ago also GHSA-2w7w-2j92-44hx , EUVD-2021-0909
- cvss
- 5.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
This affects all versions before 10.1.14 and from 10.2.0 to 10.2.4 of package com.typesafe.akka:akka-http-core. It allows multiple Transfer-Encoding headers.
Patch / fix
- maven com.typesafe.akka:akka-http-core 10.1.14, 10.2.4
- lightbend akka-http 10.1.14, 10.2.4
- github.com/akka/akka-http@e3a4935 commit
- github.com/akka/akka-http#3754 pull request
Exploit prediction
0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.0 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| NVD | 2.0 | 6.4 | AV:N/AC:L/Au:N/C:P/I:P/A:N |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | com.typesafe.akka:akka-http-core | >=10.2.0, <10.2.4 <10.1.14 |
10.2.4 10.1.14 |
Affected products
- n/a com.typesafe.akka:akka-http-core
Classification
- Weakness
-
- CWE-444 Inconsistent Interpretation of HTTP Requests
References
-
github.com
/akka/akka-http/pull/3754%23issuecomment-779265201
web, broken-link
-
github.com
/akka/akka-http/commit/e3a4935151c91cee28e65e6b894dd50839ef9d34
web
-
snyk.io
/vuln/SNYK-JAVA-COMTYPESAFEAKKA-1075043
web, broken-link
-
nvd.nist.gov
/vuln/detail/CVE-2021-23339
advisory
-
doc.akka.io
/docs/akka-http/10.1/security/2021-02-24-incorrect-handling-of-Transfer-Encoding-header.html
web
Sources
- CVE List CVE-2021-23339
- GitHub Advisory GHSA-2w7w-2j92-44hx
- NVD CVE-2021-23339
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