Malicious PDF — malware analysis report

Static analysis result for SHA-256 31356773b0ced589…

MALICIOUS

PDF

55.0 KB Created: 2020-08-13 22:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: def6888947d9cbdc165f93836505a56d SHA-1: 9032073b0cf4326e75e29040be89495357e2a4f7 SHA-256: 31356773b0ced589ac4a5bf8de9ab0e6c83d877ce42959a459ea72a87d05dc57
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a link to a known malicious redirector, ttraff.ru, which is likely used to obscure the final destination of the malicious payload. The document body, though heavily obfuscated, contains the same URL. The presence of a large number of external PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute the malicious PDF. The ML classifier strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=literature+quiz+questions+and+answers+2019
    • http://files.manaserigallery.com/uploads/1/3/0/8/130814680/afc7d46bcb.pdf
    • http://files.armadapalcamp.org/uploads/1/3/1/6/131606393/revedezodilupik.pdf
    • http://barode.leewardelite.com/uploads/1/3/1/3/131398097/fe9a4.pdf
    • http://fovusufow.emilyweihing.com/uploads/1/3/0/7/130776031/faxodutegok.pdf
    • https://cdn.shopify.com/s/files/1/0427/5778/3718/files/37901298943.pdf
    • https://cdn.shopify.com/s/files/1/0433/2155/7150/files/belosufopolivegowefeselo.pdf
    • https://cdn.shopify.com/s/files/1/0437/5986/1909/files/que_es_densidad_en_quimica.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/xuxovozukirofavekejob.pdf
    • https://cdn.shopify.com/s/files/1/0434/7245/3797/files/20176203316.pdf
    • https://cdn.shopify.com/s/files/1/0430/5672/6170/files/96114555428.pdf
    • https://cdn.shopify.com/s/files/1/0431/5722/5638/files/snap_on_welder.pdf
    • https://cdn.shopify.com/s/files/1/0434/5770/8193/files/a_wrinkle_in_time_movie_activities.pdf
    • https://cdn.shopify.com/s/files/1/0429/9289/4115/files/93942637257.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00009995.bin
696ef78137273826133dce108c7172b242ece57854b8bc65d757e7c30ac61a90
pdf-font-stream PDF embedded font (sfnt) at offset 0x9995 5476 bytes
font_01_sfnt_off0000ac5c.bin
b5e8fde051869735dbad4b5be3f3c18de8c4e9dbd28592b758ba2870231346ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xAC5C 10076 bytes