Bug 1854328 (CVE-2020-5238) - CVE-2020-5238 cmark-gfm: Exponential time to parse certain inputs could lead to DoS
Summary: CVE-2020-5238 cmark-gfm: Exponential time to parse certain inputs could lead ...
Alias: CVE-2020-5238
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1854329 1855805 1865911
Blocks: 1854330
TreeView+ depends on / blocked
Reported: 2020-07-07 08:08 UTC by Marian Rehak
Modified: 2021-05-18 20:34 UTC (History)
1 user (show)

Fixed In Version: ghc-cmark-gfm 0.29.0.gfm.1
Doc Type: If docs needed, set a value
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Clone Of:
Last Closed: 2021-05-18 20:34:00 UTC

Attachments (Terms of Use)

Description Marian Rehak 2020-07-07 08:08:18 UTC
The table extension in GitHub Flavored Markdown before version 0.29.0.gfm.1 takes O(n * n) time to parse certain inputs. An attacker could craft a markdown table which would take an unreasonably long time to process, causing a denial of service. This issue does not affect the upstream cmark project.

Upstream Advisory:


Comment 1 Marian Rehak 2020-07-07 08:09:03 UTC
Created ghc-cmark-gfm tracking bugs for this issue:

Affects: fedora-all [bug 1854329]

Comment 6 errata-xmlrpc 2021-05-18 16:32:28 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1972 https://access.redhat.com/errata/RHSA-2021:1972

Comment 7 Product Security DevOps Team 2021-05-18 20:34:00 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):


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