PDF malware analysis — malicious · 876ec8998435e6b7

MALICIOUS

PDF

25.1 KB Created: 2011-72-51 03:25:00 Authoring application: String.fromCharCode

MD5: 16e8b6bff004d21e8bd73f3dad0cf391 SHA-1: c1dd3dda97a05de86496a9e9a7dd7520e336f0cc SHA-256: 876ec8998435e6b748bbc7848b53f6ad4e953fe5dec2efdb8e23a48b1cc614e1

346 Risk Score

Malware Insights

MITRE ATT&CK

T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

This PDF document leverages multiple critical vulnerabilities (CVE-2009-4324, CVE-2009-0927, CVE-2007-5659, CVE-2008-2992) by using arithmetic operations on metadata fields to construct and execute JavaScript. The embedded JavaScript, particularly the 'info_arithmetic_stage_000.js' file, is designed as a stager, likely to download and execute a second-stage payload. The use of String.fromCharCode and eval() further indicates obfuscation aimed at evading detection.

Heuristics 10

media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324

PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927

PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659

PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992

PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
eval() call high PDF_EVAL

eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
PDF metadata arithmetic JavaScript stager high PDF_INFO_ARITHMETIC_JS_STAGER

PDF metadata hides JavaScript as arithmetic character-code tokens inside document information fields, then a launcher rebuilds it with String.fromCharCode and eval. The decoder is gated on metadata access from the launcher, a large arithmetic token table, and recovered exploit-like JavaScript.
JavaScript action low PDF_JAVASCRIPT

PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
Embedded JS stream low PDF_JS

PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
String.fromCharCode low PDF_FROMCHARCODE

String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules.
Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE

One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

Filename	Kind	Source	Size
`javascript_obj0001_000.js` `e01271ec6dbbe7d7d5563bdc96130416c7871c3533f3742bb2115c8fc26ce884`	pdf-javascript-stream	PDF /JS object 1 at offset 0x6261	302 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 1 eval/decoder/string-building token(s).
`info_arithmetic_stage_000.js` `0019616a967b4023fe4db184b86527315189e27cc4131d60ab6724b4fe53c255`	deobfuscated-js	PDF /Info Title arithmetic JavaScript at offset 0x23	3636 bytes
Detection ClamAV: No threats found Obfuscation or payload: likely Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).

Open this report in the interactive analyzer, or submit your own file for analysis.