CVE-2026-87766 (GCVE-0-2026-87766)
Vulnerability from cvelistv5 – Published: 2026-09-09 08:34 – Updated: 2026-09-09 09:59
VLAI
EPSS
VEX
Title
Bubblewrap: bubblewrap: symlink traversal via /oldroot allows writing files outside sandbox during setup
Summary
A flaw was found in bubblewrap. During sandbox setup, creating files or directories under the new root can follow a parent symlink onto the host via /oldroot, writing attacker-chosen paths outside the sandbox as the launching user. This happens before the sandboxed process starts. This issue is GHSA-pxhw-h44j-8pfx. It is fixed in bubblewrap 0.12.0.
Severity
8.8 (High)
CWE
- CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-87766 | vdb-entryx_refsource_REDHAT |
| https://bugs.debian.org/1145655 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2530542 | issue-trackingx_refsource_REDHAT |
| https://github.com/containers/bubblewrap/releases… | |
| https://github.com/containers/bubblewrap/security… | |
| https://www.openwall.com/lists/oss-security/2026/… |
Impacted products
4 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10
|
||
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8
|
||
| Red Hat | Red Hat Enterprise Linux 9 |
cpe:/o:redhat:enterprise_linux:9
|
||
| Red Hat | Red Hat Hardened Images |
cpe:/a:redhat:hummingbird:1
|
Date Public
2026-09-09 00:00
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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