Malicious PDF — malware analysis report

Static analysis result for SHA-256 eff0b8b7a77665a1…

MALICIOUS

PDF

43.0 KB Created: 2020-08-18 22:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27a023397acece6be764efcb32332332 SHA-1: 21bef74f0b92e38a605f054b474327442cd354c9 SHA-256: eff0b8b7a77665a128cacf81246015305dd0213dffbc05fef6478ff059bd07be
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Phishing: Spearphishing Attachment T1059.001 Command and Scripting Interpreter: PowerShell

The PDF contains embedded links, one of which, 'https://ttraff.ru/pify?keyword=tcs+written+test+papers', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains text related to 'Tcs written test papers', suggesting a lure. The presence of numerous other PDF links, many hosted on Shopify, indicates a link farm strategy, likely to improve search engine ranking for malicious content. The ML classifier strongly supports the malicious nature of this PDF.

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=tcs+written+test+papers
    • http://burakok.missouriinstituteofhypnotherapy.com/uploads/1/3/2/7/132710776/xopazowuv_xukefef_reriva.pdf
    • http://rapisujan.passivehabits.com/uploads/1/3/2/3/132302720/ab76593.pdf
    • http://files.alizarothdmt.com/uploads/1/3/1/3/131379824/f0c6fbd.pdf
    • http://lipopox.poseidonsporthorses.com/uploads/1/3/0/8/130874222/xelejevanagamen.pdf
    • http://gojudu.atticus-guidance.com/uploads/1/3/0/8/130874493/268183.pdf
    • https://cdn.shopify.com/s/files/1/0437/7129/7943/files/masobavovipukero.pdf
    • https://cdn.shopify.com/s/files/1/0438/4364/9698/files/mavuxiriral.pdf
    • https://cdn.shopify.com/s/files/1/0431/9599/0175/files/sebozidolizibomabe.pdf
    • https://cdn.shopify.com/s/files/1/0430/2117/2897/files/beginner_vocabulary_games.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/57896919986.pdf
    • https://cdn.shopify.com/s/files/1/0428/5900/4070/files/cloud_9_start_postgres.pdf
    • https://cdn.shopify.com/s/files/1/0432/1456/9640/files/11364938158.pdf
    • https://cdn.shopify.com/s/files/1/0449/5589/3928/files/folexerulafoj.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_off00006648.bin
48feb071535623449c533b4181fe537ca6f6a9a03da548104a743f3ebf67d6b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x6648 4936 bytes
font_01_sfnt_off0000772d.bin
2f7411cb34b757d82eacab0dc3fddbb13224b8d7313998f5e353592d216a7e48
pdf-font-stream PDF embedded font (sfnt) at offset 0x772D 12524 bytes