CVE-2026-74767

Unbounded DAA Decompression in Pandora Allows Denial of Service via Decompression Bomb

Published Aug 15, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
Pandora contains a denial-of-service vulnerability in its handling of DAA (Direct Access Archive) files. When extracting the internal ISO image from a DAA archive, compressed chunks were decompressed using zlib.decompress() without enforcing a limit on the resulting uncompressed data.


An attacker able to submit a crafted DAA file containing highly compressed data could cause Pandora to decompress a relatively small input into a very large amount of data in memory. Because the decompressed chunks are accumulated to construct the internal ISO image, this could result in excessive memory consumption and potentially CPU exhaustion, causing the extraction worker to become unresponsive, terminate, or affect the availability of the Pandora service.


The patch introduces bounded decompression using decompressobj().decompress() with max_extracted_filesize, verifies the cumulative size of decompressed chunks, and raises a dedicated ZipBomb exception when the configured limit is exceeded. Pandora then aborts extraction and reports the file as too large.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Pandora-analysis
Pandora-analysis pandora
Vendors & Products Pandora-analysis
Pandora-analysis pandora
Type Values Removed Values Added
Description Pandora contains a denial-of-service vulnerability in its handling of DAA (Direct Access Archive) files. When extracting the internal ISO image from a DAA archive, compressed chunks were decompressed using zlib.decompress() without enforcing a limit on the resulting uncompressed data. An attacker able to submit a crafted DAA file containing highly compressed data could cause Pandora to decompress a relatively small input into a very large amount of data in memory. Because the decompressed chunks are accumulated to construct the internal ISO image, this could result in excessive memory consumption and potentially CPU exhaustion, causing the extraction worker to become unresponsive, terminate, or affect the availability of the Pandora service. The patch introduces bounded decompression using decompressobj().decompress() with max_extracted_filesize, verifies the cumulative size of decompressed chunks, and raises a dedicated ZipBomb exception when the configured limit is exceeded. Pandora then aborts extraction and reports the file as too large.
Title Unbounded DAA Decompression in Pandora Allows Denial of Service via Decompression Bomb
Weaknesses CWE-434
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
CIRCL
Published
Updated
Aug 17, 2026, 7:40 PM
Reserved
Aug 15, 2026, 9:56 PM
Status
Awaiting Analysis
Published
Aug 15, 2026, 10:16 PM
Modified
Aug 26, 2026, 4:49 PM