CVE-2021-42697 - Vulnerability Details - OpenCVE

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.

Published: 2021-11-02

Score: 7.5 High

EPSS: 36.1% Moderate

KEV: No

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

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.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

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

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.

The EPSS score is 0.36139.

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

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-11-02T21:44:54.000Z

Updated: 2024-08-04T03:38:50.142Z

Reserved: 2021-10-18T00:00:00.000Z

Link: CVE-2021-42697

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-11-02T22:15:08.957

Modified: 2026-06-17T04:09:58.213

Link: CVE-2021-42697

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-674
Uncontrolled Recursion

{"containers": {"cna": {"affected": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "descriptions": [{"lang": "en", "value": "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."}], "problemTypes": [{"descriptions": [{"description": "n/a", "lang": "en", "type": "text"}]}], "providerMetadata": {"dateUpdated": "2022-05-11T17:06:20.000Z", "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "shortName": "mitre"}, "references": [{"tags": ["x_refsource_MISC"], "url": "https://akka.io/blog/"}, {"tags": ["x_refsource_MISC"], "url": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"}, {"tags": ["x_refsource_MISC"], "url": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released"}, {"tags": ["x_refsource_MISC"], "url": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released"}, {"tags": ["x_refsource_MISC"], "url": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html"}], "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "cve@mitre.org", "ID": "CVE-2021-42697", "STATE": "PUBLIC"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "n/a", "version": {"version_data": [{"version_value": "n/a"}]}}]}, "vendor_name": "n/a"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "value": "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."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "n/a"}]}]}, "references": {"reference_data": [{"name": "https://akka.io/blog/", "refsource": "MISC", "url": "https://akka.io/blog/"}, {"name": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html", "refsource": "MISC", "url": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"}, {"name": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released", "refsource": "MISC", "url": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released"}, {"name": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released", "refsource": "MISC", "url": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released"}, {"name": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html", "refsource": "MISC", "url": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html"}]}}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T03:38:50.142Z"}, "title": "CVE Program Container", "references": [{"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://akka.io/blog/"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html"}]}]}, "cveMetadata": {"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "assignerShortName": "mitre", "cveId": "CVE-2021-42697", "datePublished": "2021-11-02T21:44:54.000Z", "dateReserved": "2021-10-18T00:00:00.000Z", "dateUpdated": "2024-08-04T03:38:50.142Z", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.1"}

{"affected": [{"affectedData": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "source": "cve@mitre.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:akka:http_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "A9CC0F38-FFB5-4018-876D-6A3942B897D8", "versionEndExcluding": "10.1.15", "versionStartIncluding": "10.1.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:akka:http_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "26F742DD-9B4F-401A-B367-99F5A9050A71", "versionEndExcluding": "10.2.7", "versionStartIncluding": "10.2.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "Akka HTTP 10.1.x antes de 10.1.15 y 10.2.x antes de 10.2.7 pueden encontrar agotamiento de la pila mientras analizan las cabeceras HTTP, lo que permite a un atacante remoto llevar a cabo un ataque de denegaci\u00f3n de servicio mediante el env\u00edo de una cabecera User-Agent con comentarios profundamente anidados"}], "id": "CVE-2021-42697", "lastModified": "2026-06-17T04:09:58.213", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "MEDIUM", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "PARTIAL", "baseScore": 5.0, "confidentialityImpact": "NONE", "integrityImpact": "NONE", "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-11-02T22:15:08.957", "references": [{"source": "cve@mitre.org", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html"}, {"source": "cve@mitre.org", "tags": ["Vendor Advisory"], "url": "https://akka.io/blog/"}, {"source": "cve@mitre.org", "tags": ["Release Notes", "Vendor Advisory"], "url": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released"}, {"source": "cve@mitre.org", "tags": ["Release Notes", "Vendor Advisory"], "url": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released"}, {"source": "cve@mitre.org", "tags": ["Vendor Advisory"], "url": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://akka.io/blog/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Release Notes", "Vendor Advisory"], "url": "https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Release Notes", "Vendor Advisory"], "url": "https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-674"}], "source": "nvd@nist.gov", "type": "Primary"}]}