Bug 2524366 - CVE-2026-55620 nushell: eml_parser: Denial of Service via crafted email headers [epel-all]
Summary: CVE-2026-55620 nushell: eml_parser: Denial of Service via crafted email heade...
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Fedora EPEL
Classification: Fedora
Component: nushell
Version: epel9
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: ---
Assignee: Michel Lind
QA Contact:
URL:
Whiteboard: {"flaws": ["8158df7f-7686-427d-b2b2-d...
Depends On:
Blocks: CVE-FalsePositive-CrossEcosystem CVE-Incorrect-Version, CVE-Misfiled-Version CVE-2026-55620
TreeView+ depends on / blocked
 
Reported: 2026-08-26 11:49 UTC by Vladimir Vasilev
Modified: 2026-09-10 11:45 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2026-09-10 11:45:03 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)

Description Vladimir Vasilev 2026-08-26 11:49:27 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

eml_parser serves as a python module for parsing eml files and returning various information found in the e-mail as well as computed information. Prior to 3.0.2, eml_parser.routing.noparenthesis in eml_parser/routing.py removes parenthesized CFWS comments from Received: headers with a regex-based fix-point loop whose running time is quadratic in the nesting depth. A single Received: header with 5,000 nested parentheses causes approximately 1.3 seconds of CPU saturation per parsed message, and doubling the nesting depth approximately quadruples the running time. An attacker can submit relatively small EML files that consume multiple seconds of processing time, causing worker latency, queue backpressure, and possible service-level outages in synchronous gateways, sandboxes, and real-time triage pipelines. This issue is fixed in version 3.0.2.

Comment 1 Michel Lind 2026-09-04 16:34:21 UTC
Reassigning from `epel10` to `epel9`: Bug filed against a branch the package never shipped on.

Comment 2 Michel Lind 2026-09-10 11:45:03 UTC
This CVE is for a different package in a different ecosystem that happens to share a similar name


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