Skip to content
Fencer Vulns
high 7.5

CVE-2017-18361 json

Pylons Colander Denial of Service vulnerability

published 2019-02-01 7 y ago modified 2026-06-17 4 mo ago also GHSA-rv95-4wxj-6fqq , PYSEC-2019-167 , EUVD-2019-0030

cvss
7.5
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.1%
EPSS 2.1% chance of exploitation in 30 days, percentile 81%
public exploits
0
none known

Summary

In Pylons Colander through 1.6, the URL validator allows an attacker to potentially cause an infinite loop thereby causing a denial of service via an unclosed parenthesis.

Patch / fix

  • pypi colander 1.7.0
  • python-colander openSUSE Tumbleweed 2.0-2.4
  • python-colander openSUSE Tumbleweed 2.0-1.3

opensuse advisories openSUSE-SU-2026:12004-1openSUSE-SU-2024:14136-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2017-18361 updated cvss 5.3

python-colander: infinite loop in the URL validator

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.07% chance of exploitation in the next 30 days, higher than 81% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/Pylons/colander/issues/290 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.0 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P
GitHub 3.0 7.5 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
pypi colander
<1.7.0
1.7.0

Classification

Weakness
  • CWE-835 Loop with Unreachable Exit Condition

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.