Malicious PDF — malware analysis report

Static analysis result for SHA-256 979b88c10f82550e…

MALICIOUS

PDF

88.6 KB Created: 2021-07-07 15:54:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fb6a4273754848453fa9da0878d90a27 SHA-1: 955be57ab17b880516aad2154e874bc17ee8c8f6 SHA-256: 979b88c10f82550e9279b85432af43258f6dc10c04b86523e26b0ccc3f312b96
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://pixomot.ru/uplcv?utm_term=free+pdf+for+bank+exams
    • http://dominopark.pl/public/upload/ckfinder//userfiles/files/69134160291.pdf
    • https://holocaustresearch.pl/nowy/photo/file/nalawegajovukokituli.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607232ad79287---barifapumamomaselokela.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/16096097d0f50e---guburivolijus.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/ad558a153763a603c59182d080aab478/riroxasedifuzavadipaxewuk.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/1241s32kgshbmgif0mic66na14/64943994132.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160784d8c47725---15688720699.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/3692a40ecf0e62e176d2c8261e1a0604/92119915520.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/1957575afad7710afa7654989120de9b/22758954912.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/633d979554f81a0137ed7bb7a26c4fd8/tunab.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f07550d232---rakilazopager.pdf
    • https://himalayanthailand.com/image/upload/File/wututorima.pdf
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/s6akreab35n2imbn92tlb0g6i0/32253163070.pdf
    • http://younewstoday.com/task/userimages/file/68702879304.pdf
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/nizofuxax.pdf
    • http://g-shocktou.com/user_file/file/vexinufajukepug.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab2d2f17934---4444819674.pdf
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/wudirituzadok.pdf
    • http://hgbs.de/userfiles/file/29153860542.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af617d278ed---30025681388.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/39mjcsabsdi3il1k7ij7f3kddd/xasona.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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F5 16792 bytes
font_01_sfnt_off00011007.bin
4722e863611ef1c5dd44f15f28fc75455e6142bcff1e42b5dcec41c24a219099
pdf-font-stream PDF embedded font (sfnt) at offset 0x11007 17228 bytes
font_02_sfnt_off00013d18.bin
1ed2a3c12cd23f76df88c116ac0478298093b76e9384c9479f8b70246bc09c2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D18 10736 bytes