CVE-2021-42697

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Published Nov 2, 2021 CVSS 3.1 · 7.5 High EPSS 36.1% KEV · Not listed

Description

Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote attacker to conduct a Denial of Service attack by sending a User-Agent header with deeply nested comments.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:akka:http_server::::::::
	cpe:2.3:a:akka:http_server::::::::

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
Github GHSA	GHSA-3hw2-h67c-wq66	Uncontrolled Recursion in Akka HTTP

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 36.1% (36.139% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html
https://akka.io/blog/
https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released
https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released
https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html

History

No history.

Subscriptions

Akka Http Server

Weaknesses

CWE-674

Sources

CVE record Updated: Aug 4, 2024, 3:38 AM

Status: PUBLISHED
Assigner: mitre
Published: Nov 2, 2021, 9:44 PM
Updated: Aug 4, 2024, 3:38 AM
Reserved: Oct 18, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 4:09 AM

Status: Modified
Published: Nov 2, 2021, 10:15 PM
Modified: Jun 17, 2026, 4:09 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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