Malicious PDF — malware analysis report

Static analysis result for SHA-256 20d21fff35b5337d…

MALICIOUS

PDF

80.2 KB Created: 2021-06-11 17:22:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 627194e0104909fbb7e5246394fdfae0 SHA-1: 5dbb47735404d843f0f11a384688c4769b392e17 SHA-256: 20d21fff35b5337dfa61670154826e7136150d3424a6cb53f5c393357223a569
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution, disguised as a search result for a PDF download. No scripts were extracted, but the presence of external URIs and compromised CMS uploads points to a distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://catamma.ru/uplcv?utm_term=carnatic+music+varnam+book+pdf+download PDF link annotation
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1609902dea64ac---13932285477.pdfIn PDF document text
    • https://semut73.com/contents//files/zudawunalorafib.pdfIn PDF document text
    • http://honda-vo.com/upload/file/xoxudewilajil.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/1e7414dc49a307f6b1b5cef598c0b550/49916558546.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/27f3cf722cf5ae41fdc1b80593a39526/4271962891.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/8f39e319e23c218ed5c7bbb99f3a18df/sidoninivodadoxo.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/pilumezumikalulota.pdfIn PDF document text
    • https://hfdjet.com/wp-content/plugins/super-forms/uploads/php/files/188f82bd803e867a2c167c71d9ede97b/55837078903.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/ksurfa32qq2hqmi81i615sdejm/lerubifovadukin.pdfIn PDF document text
    • http://alamansyria.com/userfiles/file/sedejipibirimura.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/4e832d5f4774f952a0757646bbcccad0/64216469648.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf88a08783e---90522150651.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/a07deb80e5bdcc3b13993cf79840c07b/18452875932.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608827f482743---25671393952.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/ioutri27vmrptiphih8uj2o6b7/72305194101.pdfIn PDF document text
    • https://inncredel.com/uploads/85886096446.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/96899758559.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA00 5564 bytes
SHA-256: 57dcc3f949b6d04d14f9604de23b1ee15961312d3bca0b0eaf6e8d783cf6c62e
font_01_sfnt_off00010ce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE6 10840 bytes
SHA-256: d133125823f775d7c1cda9ef9342fcb0a0042ed40ed1381709519065bc5f2e2e