Malicious PDF — malware analysis report

Static analysis result for SHA-256 a844bb93d2466ca0…

MALICIOUS

PDF

5.8 KB Created: 2008-09-24 19:47:56 Authoring application: Adobe (via Notepad)
MD5: 4de6ccf3559040c23db42f8ca8007df5 SHA-1: 9b6c781e824b3fe554f77ec3bafecedf1f91f664 SHA-256: a844bb93d2466ca08d3a64fa763ac52fa0b9dd2027f8fba0e5d1fe44d21fecc3
358 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

The PDF file contains multiple critical heuristic firings indicating exploits for CVE-2009-0927, CVE-2007-5659, and CVE-2008-2992. These exploits target Adobe Reader and are used to execute embedded JavaScript. The extracted JavaScript files, particularly 'legacy_pdfkit_stage_000.js' and 'legacy_pdfkit_stage_001.js', are identified as deobfuscated exploit stages by ClamAV, suggesting they are responsible for downloading and executing further malicious content. The presence of multiple exploit triggers and deobfuscated JavaScript stages strongly indicates a malicious PDF designed for exploitation.

Heuristics 9

  • 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)
  • ClamAV: Pdf.Exploit.Agent-35931 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35931
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
913f3c653d1e4e6bcbc91dcaf4122e81a0f0947b36e84a1dcd2cd9383a92ee0a
pdf-javascript-stream PDF /JS object 6 at offset 0x1370 906 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
ccc2f5585ed7f714c5d48b19d5954417a5e24b8ed4a6281a2d4fae59f881cf67
deobfuscated-js metadata placeholder percent-decoded JavaScript at offset 0x16E 4953 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
15ffdefc9e83fcac2088a6af623ffec7776cec77dc08116b1b357e86425a7a15
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x16E 4949 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).