Vulnerability-Lookup

UBUNTU-CVE-2026-88834 (CVE-2026-88834)

Vulnerability from osv_ubuntu – Published: 2026-10-15 00:00 – Updated: 2026-10-15 00:00 – Source website

Details

A flaw was found in BusyBox's httpd web server. When configured with system password authentication, a user existence oracle may exist in certain build configurations. An attacker could distinguish existing from non-existing usernames by observing authentication failure behavior. Impact is limited to username enumeration and requires non-default compile options or uncommon password file states; default BusyBox builds with shadow password support are not affected.

Severity

3.7 (Low)


                    
                      CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-88834	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-88834	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2531348	REPORT
	https://access.redhat.com/security/cve/CVE-2026-88834	REPORT

JSON

To clipboard

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  "affected": [
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      "ecosystem_specific": {
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            "binary_version": "1:1.21.0-1ubuntu1.4+esm1"
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  "id": "UBUNTU-CVE-2026-88834",
  "modified": "2026-10-15T00:00:00Z",
  "published": "2026-10-15T00:00:00Z",
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  "schema_version": "1.7.0",
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}

CVE-2026-88834 (GCVE-0-2026-88834)

Vulnerability from cvelistv5 – Published: 2026-10-13 16:58 – Updated: 2026-10-13 17:16

Title

Busybox: busybox: httpd user existence oracle in non-default shadow-disabled builds

Summary

Severity

3.7 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-13 17:16 UTC

CWE

CWE-203 - Observable Discrepancy

Assigner

redhat CNA under the redhat root

CNA scorecard B 82/100 over 1036 records in the last 180 days details

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-88834	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2531348	issue-trackingx_refsource_REDHAT

Impacted products

1 product

Vendor	Product	Version
Red Hat	Red Hat Hardened Images	cpe:/a:redhat:hummingbird:1

Date Public

2026-10-13 13:49

Credits

Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.

Show details on NVD website

JSON

To clipboard

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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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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