Malicious PDF — malware analysis report

Static analysis result for SHA-256 981f365d84bffae6…

MALICIOUS

PDF

66.2 KB Created: 2021-06-13 03:26:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: d6f156dee88f86a092c596d15ecb118d SHA-1: 4efe39bc7549ab249b903b26a79f7ed45288863b SHA-256: 981f365d84bffae6134d9398b67d42711f8b40b20d4d5aa2c20ed02697f54920
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the heuristic firings and URL patterns are sufficient to assess the attack pattern.

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://irlanc.ru/uplcv?utm_term=garfield+scary+scavenger+hunt PDF link annotation
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab923f42283---dezux.pdfIn PDF document text
    • https://etadelloro.it/images/file/58071440346.pdfIn PDF document text
    • http://alexanderjamesbackcatalogue.com/userfiles/file/87414052963.pdfIn PDF document text
    • https://atphp.ch/userfiles/file/mujakurov.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d6eb50833---64048730851.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607476c13714d---58892748830.pdfIn PDF document text
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021060301295980554.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160af3fb378c43---50294647517.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a8f260e3d01---godirovuxaletasawebovekug.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160909f946001b---gudiketepagudegoj.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/pihuhrcun3o9oc3slv3aqu08cq/zewenogum.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/cd21c3cb2549dcc53a80577fc1c698d4/rekelijorilapunesinox.pdfIn PDF document text
    • https://argumentua.com/i/file/99913954398.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160924a5cb0fb9---jenurumefobiwuxiluzodoso.pdfIn PDF document text
    • http://carzip.biz/files/uploads/files/jokepigebamo.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/mf2knu6hmipuff3apnh72h8de8/lijaxusifixiduvog.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_off0000c4a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A1 5476 bytes
SHA-256: df51fc0950f73f17b87327498b423037ad5d0343bda638596adfba47c92ae026
font_01_sfnt_off0000d74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74B 10732 bytes
SHA-256: 7093c21905b045b6edbb59ef457e151addee82b9fb35f2f49c1f1b91ce6cba2a