GHSA-f4w8-cv6p-x6r5 · Severity: high · Ecosystem: pip — Pillow Denial of Service by Uncontrolled Resource Consumption
Pillow before 8.1.2 allows attackers to cause a denial of service (memory consumption) because the reported size of a contained image is not properly checked for a BLP container, and thus an attempted memory allocation can be very large.
Conclusion & alert: CVE-2021-27921 is rated Moderate Risk (63/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.17%). Core evidence: EPSS rose +2.75% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.42% | 3.17% | +2.75% |
| 2 | 2025-12-24 | 0.79% | 0.42% | -0.37% |
| 3 | 2025-11-21 | — | 0.79% | — |
Full EPSS history (22 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.1 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
GHSA-f4w8-cv6p-x6r5 · Severity: high · Ecosystem: pip — Pillow Denial of Service by Uncontrolled Resource Consumption
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
— | CVE-2021-27921: 1 source package rows (py3-pillow); 8 state rows across 8 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community, edge-main); fixed 8, open 0. | https://security.alpinelinux.org/vuln/CVE-2021-27921 |
debian
|
not yet assigned | CVE-2021-27921 not yet assigned priority: Debian including 1 source packages (pillow), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2021-27921 |
gentoo
|
normal | CVE-2021-27921: 1 GLSA(s) (202107-33), 1 atom(s) (dev-python/pillow); latest impact normal. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-27921 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2021-27921 |
suse
|
high | CVE-2021-27921 severity important: SUSE including 26 source package names (python-Pillow, python-Pillow-5.2.0-3.8.1, …), 52 product×package rows across 20 product lines (HPE Helion OpenStack 8, SUSE Liberty Linux 8, … (20 product lines)): Fixed 28, Known Not Affected 24. | https://www.suse.com/security/cve/CVE-2021-27921/ |
ubuntu
|
medium | CVE-2021-27921 medium priority: Ubuntu including 3 source packages (pillow, pillow-python2, python-imaging), 48 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 28, not-affected 12, released 4, needs-triage 3, ignored 1. | https://ubuntu.com/security/CVE-2021-27921 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| python | pillow | < 8.1.1 | cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:* |
| fedoraproject | fedora | 32 | cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* |
| fedoraproject | fedora | 33 | cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* |
| fedoraproject | fedora | 34 | cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* |