Bug 2558580 (CVE-2026-114501)

Summary:	CVE-2026-114501 pillow: Pillow: Information disclosure via improper memory alignment during Arrow export
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	alinfoot, anpicker, anthomas, aprice, bbrownin, cmyers, dfreiber, dnakabaa, doconnor, drow, dschmidt, dtrifiro, ebourniv, ehelms, ggainey, hasun, ilpinto, jburrell, jfula, jlanda, jmitchel, jowilson, jpasqual, jsamir, juwatts, jwong, kaycoth, kshier, lcouzens, ltomasbo, mdellweg, mhayden, mhulan, mwoodson, nmoumoul, nyancey, oezr, omaciel, ometelka, osousa, pcreech, ptisnovs, rbobbitt, rchan, rhel-process-autobot, sbunciak, sdoran, simaishi, smallamp, stcannon, syedriko, tmalecek, vkumar, watson-tool-maintainers, weaton, xdharmai, yguenane, ykashtan
Target Milestone:	---	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in Pillow. This vulnerability can lead to information disclosure when exporting images to Apache Arrow format with memory alignment enabled, as the library assumes image rows are contiguous in memory. Consequently, exported buffers may incorporate uninitialized padding or residual data from previously freed process memory. An attacker could exploit this flaw to obtain sensitive process memory or image data belonging to other users.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2026-10-21 21:42:11 UTC

Pillow is a Python imaging library. From 11.2.1 until 13.0.0, Arrow export assumes that an image's rows are tightly contiguous and exports from im->blocks[0].ptr even when PILLOW_ALIGNMENT makes aligned_linesize include row padding or an aligned offset before the first row. The resulting Arrow buffer can include uninitialized padding, bytes preceding the first row, or stale heap contents from previously freed images. Applications that configure alignment and export images to Arrow can therefore disclose one user's pixels or other process memory to another user. This issue is fixed in version 13.0.0.