CVE-2018-1061
python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (4.74%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method. An attacker could use this flaw to cause denial of service.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 4.74% probability · 92th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- python/python · debian/debian linux · redhat/ansible tower · redhat/enterprise linux desktop · redhat/enterprise linux server · redhat/enterprise linux workstation · canonical/ubuntu linux · fedoraproject/fedora
- Source
- secalert@redhat.com
EPSS 4.7% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
- http://www.securitytracker.com/id/1042001Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHBA-2019:0327Third Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3041Third Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3505Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:1260
- https://access.redhat.com/errata/RHSA-2019:3725
- https://bugs.python.org/issue32981Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1061Issue Tracking
- https://docs.python.org/3.5/whatsnew/changelog.html#python-3-5-6-release-candidate-1Vendor Advisory
- https://docs.python.org/3.6/whatsnew/changelog.html#python-3-6-5-release-candidate-1Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2018/09/msg00030.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2018/09/msg00031.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JSKPGPZQNTAULHW4UH63KGOOUIDE4RRB/
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbst03951en_us
- https://usn.ubuntu.com/3817-1/Third Party Advisory
- https://usn.ubuntu.com/3817-2/Third Party Advisory
- https://www.debian.org/security/2018/dsa-4306Third Party Advisory
- https://www.debian.org/security/2018/dsa-4307Third Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
- http://www.securitytracker.com/id/1042001Third Party Advisory, VDB Entry
- https://access.redhat.com/errata/RHBA-2019:0327Third Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3041Third Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3505Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:1260
- https://access.redhat.com/errata/RHSA-2019:3725
- https://bugs.python.org/issue32981Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1061Issue Tracking
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.