cbcvebase.
CVE-2021-41270
published 2021-11-24

CVE-2021-41270: Symfony/Serializer handles serializing and deserializing data structures for Symfony, a PHP framework for web and console applications and a set of reusable…

PriorityP337medium6.5CVSS 3.1
AVNACLPRLUINSUCHINAN
EPSS
1.35%
68.5th percentile
Symfony/Serializer handles serializing and deserializing data structures for Symfony, a PHP framework for web and console applications and a set of reusable PHP components. Symfony versions 4.1.0 before 4.4.35 and versions 5.0.0 before 5.3.12 are vulnerable to CSV injection, also known as formula injection. In Symfony 4.1, maintainers added the opt-in `csv_escape_formulas` option in the `CsvEncoder`, to prefix all cells starting with `=`, `+`, `-` or `@` with a tab `\t`. Since then, OWASP added 2 chars in that list: Tab (0x09) and Carriage return (0x0D). This makes the previous prefix char (Tab `\t`) part of the vulnerable characters, and OWASP suggests using the single quote `'` for prefixing the value. Starting with versions 4.4.34 and 5.3.12, Symfony now follows the OWASP recommendations and uses the single quote `'` to prefix formulas and add the prefix to cells starting by `\t`, `\r` as well as `=`, `+`, `-` and `@`.

Affected

17 ranges
VendorProductVersion rangeFixed in
debiansymfony< symfony 4.4.19+dfsg-3 (bookworm)symfony 4.4.19+dfsg-3 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
sensiolabssymfony>= 4.1.0 < 4.4.354.4.35
sensiolabssymfony>= 5.0.0 < 5.3.125.3.12
symfonyserializer>= 4.1.0 < 4.4.354.4.35
symfonyserializer>= 5.0.0 < 5.3.125.3.12
symfonysymfony
symfonysymfony
symfonysymfony>= 0 < 4.4.19+dfsg-2+deb11u14.4.19+dfsg-2+deb11u1
symfonysymfony>= 0 < 4.4.19+dfsg-34.4.19+dfsg-3
symfonysymfony>= 0 < 4.4.19+dfsg-34.4.19+dfsg-3
symfonysymfony>= 0 < 4.4.19+dfsg-34.4.19+dfsg-3
symfonysymfony>= 0 < 3.4.6+dfsg-1ubuntu0.1+esm23.4.6+dfsg-1ubuntu0.1+esm2
symfonysymfony>= 0 < 4.3.8+dfsg-1ubuntu1+esm14.3.8+dfsg-1ubuntu1+esm1
symfonysymfony>= 4.1.0 < 4.4.354.4.35
symfonysymfony>= 5.0.0 < 5.3.125.3.12

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
nvdv2.04.0MEDIUMAV:N/AC:L/Au:S/C:P/I:N/A:N
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_ubuntu5.3MEDIUM
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