CVE-2025-39835

Status: ModifiedHigh (7.8)—

In the Linux kernel, the following vulnerability has been resolved:

xfs: do not propagate ENODATA disk errors into xattr code

However, a medium error from disk may also return ENODATA. At best, this medium error may escape to userspace as "attribute not found" when in fact it's an IO (disk) error.

At worst, we may oops in xfs_attr_leaf_get() when we do:

because an ENODATA/ENOATTR error from disk leaves us with a null bp, and the xfs_trans_brelse will then null-deref it.

As discussed on the list, we really need to modify the lower level IO functions to trap all disk errors and ensure that we don't let unique errors like this leak up into higher xfs functions - many like this should be remapped to EIO.

Read full descriptionShow less

However, this patch directly addresses a reported bug in the xattr code, and should be safe to backport to stable kernels. A larger-scope patch to handle more unique errors at lower levels can follow later.

(Note, prior to 07120f1abdff we did not oops, but we did return the wrong error code to userspace.)

Technical details traces, logs and code from the original report

ENODATA (aka ENOATTR) has a very specific meaning in the xfs xattr code;
namely, that the requested attribute name could not be found.

	error = xfs_attr_leaf_hasname(args, &bp);
	if (error == -ENOATTR)  {
		xfs_trans_brelse(args->trans, bp);
		return error;
	}

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.17%
Percentile among all scored CVEs: 6
Score date: 10/6/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Primary impactT1499.004 Application or System Exploitationimpact70 %
Secondary impactT1561.002 Disk Structure Wipeimpact60 %

Vuln. local (AV:L, PR:L) sin interacción. El kernel null-dereference en xfs_attr_leaf_get() permite DoS; manejo erróneo de errores de disco puede causar corrupción de datos.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Threat Intelligence Program Filter Network Traffic Execution Prevention Application Isolation and Sandboxing Exploit Protection Update Software

Affected technologies (2)

Debian — Debian Linux Linux — Linux Kernel

CWEs

NVD-CWE-noinfo

References

Raw JSON (NVD)

Show

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      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfs: do not propagate ENODATA disk errors into xattr code\n\nENODATA (aka ENOATTR) has a very specific meaning in the xfs xattr code;\nnamely, that the requested attribute name could not be found.\n\nHowever, a medium error from disk may also return ENODATA. At best,\nthis medium error may escape to userspace as \"attribute not found\"\nwhen in fact it's an IO (disk) error.\n\nAt worst, we may oops in xfs_attr_leaf_get() when we do:\n\n\terror = xfs_attr_leaf_hasname(args, &bp);\n\tif (error == -ENOATTR)  {\n\t\txfs_trans_brelse(args->trans, bp);\n\t\treturn error;\n\t}\n\nbecause an ENODATA/ENOATTR error from disk leaves us with a null bp,\nand the xfs_trans_brelse will then null-deref it.\n\nAs discussed on the list, we really need to modify the lower level\nIO functions to trap all disk errors and ensure that we don't let\nunique errors like this leak up into higher xfs functions - many\nlike this should be remapped to EIO.\n\nHowever, this patch directly addresses a reported bug in the xattr\ncode, and should be safe to backport to stable kernels. A larger-scope\npatch to handle more unique errors at lower levels can follow later.\n\n(Note, prior to 07120f1abdff we did not oops, but we did return the\nwrong error code to userspace.)"
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