CVE-2026-27459
Aliases:GHSA-5pwr-322w-8jr4ECHO-913b-6868-0495PYSEC-2026-2269RHSA-2026:10754DEBIAN-CVE-2026-27459CGA-2fcg-2mj9-4rq3CGA-2p8v-hwg7-jffqCGA-2xm6-wqfj-h9g8CGA-33qj-vgj7-49xgCGA-36gx-rc63-p5f5CGA-44vj-c62w-9pqfCGA-4fwj-3895-qx4fCGA-5ggx-c34c-xpgrCGA-699c-f5fr-h896CGA-6hcj-qcpc-xjx2CGA-6vfp-34gj-2w5cCGA-725q-j3mv-j9j7CGA-932w-mhxv-2j5qCGA-9rqh-rmh3-f67gCGA-c6x8-pqqf-f5w4CGA-chpv-r9xg-7gqfCGA-fw2g-8mwr-q493CGA-h94w-h435-7mfrCGA-jgvf-26h6-gg4vCGA-jmgh-2c6x-f7x5CGA-m3rv-f3qx-ch2gCGA-pqh8-hj43-3vqhCGA-279r-q8hv-8qp7CGA-2pvq-r3r5-324xCGA-2vj4-g682-rgxcCGA-39vm-28v3-h2q9CGA-3g6f-63j4-rpvqCGA-3jfg-537w-w8h5CGA-3v74-h6q3-3v6jCGA-43fh-pq9x-rpwmCGA-4657-hpfx-wm5hCGA-5m2q-6rpj-mwghCGA-5mv9-f688-x7q9CGA-5wcp-5gqf-mq9vCGA-6jgw-xhgq-7574CGA-6mhx-hqv8-8839CGA-6w36-85qx-p9gxCGA-6wvv-994h-5cc3CGA-7hv7-6w6q-ch85CGA-7xpf-8jmg-p3h9CGA-833q-3f77-4ff2CGA-8558-v7f7-xjxrCGA-85v9-95xx-2x4rCGA-8r6q-2rxf-2pf4CGA-925m-cpv9-7h56CGA-97r8-89rv-xxj9CGA-9mjw-wv36-2hhwCGA-cf8g-pp49-rgqjCGA-cj49-xqvg-cr36CGA-cw88-m7qv-62cwCGA-f64c-5gc6-x94qCGA-fj69-m73v-v4xrCGA-gm78-j82r-h3fxCGA-gq4f-2p7h-6wwmCGA-gxhh-xvg2-fm8wCGA-h2fr-g857-ffpqCGA-h98c-vxhf-rcq3CGA-hqv7-27cp-qxrmCGA-j494-5x9j-qf6fCGA-jjjx-fhr3-228jCGA-jmwj-j3hc-7q87CGA-m2v7-h54p-64vpCGA-mc2v-hjxx-9v5hCGA-mh4h-c64x-wjx9CGA-mrpx-g6m8-h95jCGA-p8mv-7p4p-g936CGA-pcvc-jfmf-jcg3CGA-q43w-xpx4-mg56CGA-r37p-p6jp-c5qxCGA-r3jj-mjgx-c59fCGA-r6qf-j6c6-8jcwCGA-r8mg-3hv3-fcp8CGA-rqf2-4h77-27jcCGA-v2vp-63qv-qv48CGA-vcfv-vp8m-6r6pCGA-vq2r-2fxr-37xmCGA-vqcg-qqf4-3v43CGA-w8fm-hx84-wjcwCGA-w8x6-hpp3-3vvvCGA-wghp-23rc-9xj4CGA-wwxx-gx2h-xxvcCGA-xwvc-vmvp-87j2CGA-h7c3-3f9g-g8qc
Advisory lineage Upstream: 0 Downstream: 20
Modified
Published: 17 Mar 2026, 23:34
Last modified:11 Sept 2026, 12:09
Vulnerability Summary
Overall Risk (default)
high
70/100 CVSS Score
9.8 CRITICAL
v3.1 (nvd)
EPSS Score
0.7% LOW
1% probability +0.68%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected
Timeline
17 Mar 2026, 23:34
Published
Vulnerability first disclosed
11 Sept 2026, 12:09
Last Modified
Vulnerability information updated
Description
pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long are now rejected.
CVSS Metrics
- v4.0•CRITICAL•Score: 9.2CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U
- v4.0•HIGH•Score: 7.2CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- v3.1•HIGH•Score: 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Trends
Current EPSS score: 0.70%• Percentile: 52%
Techniques & Countermeasures
- CWE-120•Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
Affected Systems
- chainguard•airflow-2
< 2.11.2-r2
- chainguard•airflow-3
< 3.1.8-r8
- chainguard•authentik
< 2026.2.1-r4
- chainguard•authentik-fips
< 2026.2.1-r3
- chainguard•awx
< 24.6.1-r31
- chainguard•az
< 2.84.0-r3
- chainguard•datadog-agent-7.71-core-integrations
all
- chainguard•datadog-agent-7.72-core-integrations
all
- chainguard•datadog-agent-7.73-core-integrations
< 7.73.3-r23
- chainguard•datadog-agent-7.74-core-integrations
< 7.74.1-r24
- chainguard•datadog-agent-7.75-core-integrations
all
- chainguard•datadog-agent-7.76
< 7.76.3-r41
- chainguard•datadog-agent-7.76-core-integrations
< 7.76.3-r32
- chainguard•datadog-agent-7.77-core-integrations
< 7.77.3-r5
- chainguard•datadog-agent-fips-7.71-core-integrations
< 7.71.2-r20 | < 7.71.2-r19
- chainguard•datadog-agent-fips-7.72-core-integrations
all
- chainguard•datadog-agent-fips-7.73-core-integrations
< 7.73.3-r26
- chainguard•datadog-agent-fips-7.74-core-integrations
< 7.74.1-r26
- chainguard•datadog-agent-fips-7.75-core-integrations
all
- chainguard•datadog-agent-fips-7.76-core-integrations
< 7.76.3-r32
- chainguard•datadog-agent-fips-7.77-core-integrations
< 7.77.3-r5
- chainguard•datahub-ingestion
< 1.5.0.1-r0
- chainguard•dbt-snowflake
all
- chainguard•ggshield
< 1.51.0-r1
- chainguard•gitlab-toolbox-ce-18.7
< 18.7.5-r1
- chainguard•gitlab-toolbox-ce-18.8
< 18.8.5-r2
- chainguard•gitlab-toolbox-ce-18.9
< 18.9.2-r1
- chainguard•gitlab-toolbox-ce-fips-18.7
< 18.7.5-r1
- chainguard•gitlab-toolbox-ce-fips-18.8
< 18.8.5-r1
- chainguard•gitlab-toolbox-ce-fips-18.9
< 18.9.2-r1
- chainguard•gitlab-toolbox-ce-fips-19.0
< 19.0.2-r1
- chainguard•keep-api
< 0.51.0-r0
- chainguard•keep-api-fips
< 0.51.0-r0
- chainguard•localstack
< 4.14.0-r4
- chainguard•mitmproxy
< 12.2.1-r0 | < 12.2.3-r0
- chainguard•py3-cassandra-medusa
< 0.27.0-r5
- chainguard•py3.13-duplicity
all
- chainguard•request-1276
< 0.27.0-r6
- chainguard•superset-5.0
< 5.0.0-r20
- chainguard•superset-6.0
< 6.0.0-r4
- wolfi•airflow-3
< 3.1.8-r8
- wolfi•az
< 2.84.0-r3
- wolfi•datadog-agent-7.72-core-integrations
all
- wolfi•datadog-agent-7.73-core-integrations
< 7.73.3-r23
- wolfi•datadog-agent-7.74-core-integrations
< 7.74.1-r24
- wolfi•datadog-agent-7.75-core-integrations
all
- wolfi•datadog-agent-7.76
< 7.76.3-r41
- wolfi•datadog-agent-7.76-core-integrations
< 7.76.3-r32
- wolfi•datadog-agent-7.77-core-integrations
< 7.77.3-r5
- wolfi•ggshield
< 1.51.0-r1
Showing first 50 affected entries in server-rendered view.
References (33)
- https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4
- https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408
- https://github.com/pyca/pyopenssl
- https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst
- https://nvd.nist.gov/vuln/detail/CVE-2026-27459
- https://access.redhat.com/security/cve/CVE-2026-27459
- https://bugzilla.redhat.com/show_bug.cgi?id=2448503
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27459.json
- https://access.redhat.com/errata/RHSA-2026:13512
- https://access.redhat.com/errata/RHSA-2026:10754
- https://access.redhat.com/errata/RHSA-2026:14874
- https://access.redhat.com/errata/RHSA-2026:13508
- https://access.redhat.com/errata/RHSA-2026:14873
- https://access.redhat.com/errata/RHSA-2026:14835
- https://access.redhat.com/errata/RHSA-2026:13553
- https://access.redhat.com/errata/RHSA-2026:13545
- https://access.redhat.com/errata/RHSA-2026:7224
- https://access.redhat.com/errata/RHSA-2026:11856
- https://access.redhat.com/errata/RHSA-2026:21017
- https://access.redhat.com/errata/RHSA-2026:24853
- https://access.redhat.com/errata/RHSA-2026:19375
- https://access.redhat.com/errata/RHSA-2026:22465
- https://access.redhat.com/errata/RHSA-2026:11916
- https://access.redhat.com/errata/RHSA-2026:11996
- https://access.redhat.com/errata/RHSA-2026:8437
- https://access.redhat.com/errata/RHSA-2026:48085
- https://access.redhat.com/security/updates/classification/#important
- https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_10754.json
- https://www.cve.org/CVERecord?id=CVE-2026-27459
- https://security-tracker.debian.org/tracker/CVE-2026-27459
- https://access.redhat.com/errata/RHSA-2026:48758
- https://access.redhat.com/errata/RHSA-2026:59153
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27459.json