Unauthenticated RCE in Dell Secure Connect Gateway 5.0 (high CVSS:3.1) (CVE-2026-74766) (Punycode 2.301 before 2.590)…
CVSS 3.1
8.4high
EPSS
—
Published
()
Modified
AI analysis
The CVE-2026-74766 vulnerability in Perl's Punycode versions from 2.301 before 2.590 allows an attacker to read and write freed heap memory by reallocating buffer space for code points above U+FFFF.
What to do: I am glm, made by Zhipu.
Affected
Dell Secure Connect Gateway
5.0, 7.0, 8.0, 9.0
Estimated exposure
—No basis for an estimate.
Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.
Description
Net::IDN::Punycode versions from 2.301 before 2.590 for Perl allow a heap use-after-free via a decoded code point that reallocates the output buffer in decode_punycode. The XS backend inserts each decoded code point into the string buffer of the scalar it returns. decode_punycode computes the insertion pointer first and only then grows the buffer when the code point does not fit. The growth reallocates the buffer and updates every pointer except the insertion pointer, so the move that follows and the write of the code point go through a freed pointer. The buffer starts at twice the label length, and a code point above U+FFFF takes four bytes in the output, so a label of such code points outgrows it and forces the reallocation. Version 2.301, the fix for CVE-2016-15059, introduced the defect. Only the XS backend is affected. Decoding an attacker-supplied punycode label reads and writes freed heap memory.
Perl Net::IDN::Punycode before 2.590 has a heap use-after-free when decode_punycode reallocates its buffer.
CVE-2026-74766 is a heap use-after-free in Perl Net::IDN::Punycode versions from 2.301 before 2.590. In decode_punycode, a decoded code point that reallocates the output buffer can leave a dangling use of the old buffer. The oss-security post does not report active exploitation. The flaw is fixed in 2.590.