CVE-2021-42697
HIGH
7.5
CVSS Score
Published: November 2, 2021 at 09:44 PM UTC
Updated: June 17, 2026 at 04:09 AM UTC
1 product affected across 1 vendorHTTP Server
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Severity
HIGH7.5
Exploit prediction
EPSS 36%
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
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
10.1.0 ≤ v < 10.1.1510.2.0 ≤ v < 10.2.7
Affected range stops below 10.1.15, so it looks safe — our inference, not a vendor statement
Affected range stops below 10.2.7, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (5)
x_refsource_MISCExploitThird Party AdvisoryVDB Entry
Source: [email protected]
http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.htmlx_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-releasedx_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-releasedx_refsource_MISCVendor Advisory
Source: [email protected]
https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.htmlCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-674
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