CVE-2017-2523

critical

Published 2017-05-22 · Modified 2026-05-13

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CVSS v3

9.8

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v4 NEW

—

not yet in upstream

VIR risk

10.0

Description

An issue was discovered in certain Apple products. iOS before 10.3.2 is affected. macOS before 10.12.5 is affected. tvOS before 10.2.1 is affected. watchOS before 3.2.2 is affected. The issue involves the "Foundation" component. It allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption and application crash) via crafted data.

Predictions

Exploit likelihood

97%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-42050 dos multiple verified text · 1 KB

Google Security Research · 2017-05-23

Apple macOS/iOS - NSUnarchiver Heap Corruption Due to Lack of Bounds Checking in [NSBuiltinCharacterSet initWithCoder:]

text exploit Source: Exploit-DB

Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1170

Via NSUnarchiver we can read NSBuiltinCharacterSet with a controlled serialized state.
It reads a controlled int using decodeValueOfObjCType:"i" then either passes it to
CFCharacterSetGetPredefined or uses it directly to manipulate __NSBuiltinSetTable.
Neither path has any bounds checking and the index is used to maniupulate c arrays of pointers.

Attached python script will generate a serialized NSBuiltinCharacterSet with a value of 42
for the character set identifier.

tested on MacOS 10.12.3 (16D32)


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/42050.zip

OS impact

macOS Affected 1 release

Version	Status	Fixed in
—	Affected	`10.3.2`

References

CWEs

CWE-119

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.