How severe is CVE-2018-1061?

CVE-2018-1061 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-1061 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1061?

CVE-2018-1061 primarily affects Redhat Ansible Tower. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-1061?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-1061 published?

CVE-2018-1061 was published on 2018-06-19 and last updated on 2026-06-17.

CVE-2018-1061

CVE-2018-1061 is a medium-severity vulnerability in Redhat Ansible Tower with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 5.0
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Redhat Ansible Tower
Published: 2018-06-19
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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. An attacker could use this flaw to cause denial of service.
How severe is CVE-2018-1061?: CVE-2018-1061 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-1061 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1061?: CVE-2018-1061 primarily affects Redhat Ansible Tower. In total, 24 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-1061?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-1061 published?: CVE-2018-1061 was published on 2018-06-19 and last updated on 2026-06-17.

References

Affected products (24)

cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:alpha1:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:alpha2:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:alpha3:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:alpha4:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:beta1:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:beta2:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:beta3:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:beta4:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:beta5:*:*:*:*:*:*
cpe:2.3:a:python:python:3.7.0:rc1:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:redhat:ansible_tower:3.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

203.192.232.180 (ipv4-addr)
177.53.215.134 (ipv4-addr)
5.99.196.202 (ipv4-addr)
121.164.135.251 (ipv4-addr)
120.224.15.67 (ipv4-addr)
222.88.237.152 (ipv4-addr)