CVE
Pillow denial of service in TIFF and EXIF parsing
Pillow versions before 13.0.0 are affected when an application parses TIFF or EXIF data from uploaded images, including PNG, JPEG, WebP or MPO files that call getexif() or ImageOps.exif_transpose(). Fixed in 13.0.0.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 13.0.0
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 13.0.0.
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.38% · 32nd percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 46/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
Pillow, a Python imaging library, is affected. A remote attacker who can get a small crafted TIFF or EXIF-bearing image processed, without logging in, can exhaust the process's memory and crash it, because the parser keeps excessive metadata data.
Read the original description
Pillow is a Python imaging library. From 1.0 through 12.3.0, ImageFileDirectory_v2.load() in src/PIL/TiffImagePlugin.py retains a separate bytes object for each out-of-line IFD tag value without limiting the total data read or preventing distinct tags from referencing the same file region. A small crafted TIFF or EXIF-bearing JPEG, PNG, WebP, or MPO can therefore cause memory use quadratic in the input size. TIFF and some JPEG paths trigger parsing during Image.open(), while other formats are exposed when EXIF is requested, including through getexif() or ImageOps.exif_transpose(). The declared pixel dimensions do not bound this metadata allocation, so decompression-bomb checks do not prevent process memory exhaustion. This issue is fixed in version 13.0.0.
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Unknown: Advisories don't say whether default setups are affected
- Reach20/20pillow: 177M downloads a week
- Severity8.7/10CVSS 8.7
- No patch0/5No signal
What would change the score
- Would score about 91 if added to CISA KEV
- Would score about 86 if CISA's SSVC rates exploitation active
- Would score about 51 if advisories confirm default setups are exposed
Impact
- Widely used
pillow has 177m weekly downloads.Source: pypistats.org
95.5k packages depend on pillow.Source: deps.dev
What to do
Upgrade to a fixed version: 13.0.0.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-128066 (Pillow: Memory DoS in TIFF and EXIF IFD parsing via overlapping tag data), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-128066 (entry last updated 2026-11-12):
Affected:
- python-pillow Pillow: from 1.0, fixed in 13.0.0
- PyPI package pillow: fixed in 13.0.0
Fixed versions: 13.0.0.
Conditions (all must be true for the bug to be hit):
- For PNG, JPEG, WebP or MPO EXIF data, the application must call getexif() or ImageOps.exif_transpose() (TIFF and some JPEG paths parse during Image.open()) (source: https://github.com/python-pillow/Pillow/security/advisories/GHSA-wqgw-9xfh-qf2g)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, no login, no user action.
CISA KEV: CVE-2026-128066 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-128066 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Packages (PyPI): find every lockfile in each project and run the stack.check operation of the cve.now MCP server (execute) on each one. Compare the resolved versions, not the ranges a manifest declares, with the affected versions above. Include transitive dependencies.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/python-pillow/Pillow/security/advisories/GHSA-wqgw-9xfh-qf2g
- https://github.com/python-pillow/Pillow/commit/4908edaf7f416616784c7c03d8c1a60153710ffb
- https://github.com/python-pillow/Pillow/commit/4b63dffd8a6d980fa0e21b40832fa6cbf033eacf
- https://github.com/python-pillow/Pillow/releases/tag/13.0.0
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-128066
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-128066"}.Timeline
- CVE published
- First seen by cve.now
Affected versions
- python-pillow Pillow
From 1.0 · fixed in 13.0.0
- pillowPyPI
fixed in 13.0.0
Fixed in 13.0.0 (released Oct 16, 2026, 27 days before disclosure).
The latest release, 13.0.0, is not affected.
Evidence 6
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Advisory
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Other links · 3
- Repository
- Repository
- Repository
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-128066
Is CVE-2026-128066 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
Overlapping tag data in TIFF and EXIF IFD parsing can make Pillow allocate and retain memory many times the size of the file, causing a denial of service of the process handling the input. The advisory states there is no memory corruption.Source: github.com
Which versions are affected by CVE-2026-128066?
Pillow: from 1.0 before 13.0.0. pillow (PyPI): before 13.0.0.Source: cve.now feed data
Am I affected, and how do I check?
Pillow versions before 13.0.0 are affected. TIFF and some JPEG paths parse during Image.open(), while for PNG, JPEG, WebP or MPO EXIF data the application must call getexif() or ImageOps.exif_transpose(). To check a version, run python -c "import PIL; print(PIL.__version__)" or pip show pillow.Source: github.com
How do I fix CVE-2026-128066?
Upgrade Pillow to 13.0.0 or later.Source: github.com