Malicious PDF — malware analysis report

Static analysis result for SHA-256 79a54b1bb802baba…

MALICIOUS

PDF

86.3 KB Created: 2021-07-03 17:47:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b6d0c9f2d30fcf58b5b4ae017eaa202f SHA-1: 486b54b21ef92c45e2d7c21951350fe38a83f9b4 SHA-256: 79a54b1bb802baba54407dcff1591e36fbf297f9c542c9a31f6a4e7fda7ad3ae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to multiple compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or phishing lures. The embedded URLs likely serve as the initial vector for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/cfd6af37233ea2de60e71b8879b8e2f1/laborixabomogovujis.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609952b504e52---bufigiselefapomakodejudu.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/2fa989c40021be175df4ddaf1aecba81/27820206247.pdf
    • https://service-panev.com/userfiles/18176573647.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/cc1aeed0828c5ae495f3f2e41dbb74ca/kapasibes.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9a833825c---42137702168.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16094572c470b9---bugexonabazetivopufujafo.pdf
    • https://rowadalbyt.com/userfiles/files/81199576068.pdf
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/2713a071019677c6a64abcf8092de6b6/53187785149.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc80343c22---83711284778.pdf
    • http://boisehighclassof1965.com/clients/879780/File/93636590867.pdf
    • http://candybeauty.vn/upload/files/41330512381.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/b763dbfd4c852803047e7597a7395b86/42865172149.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d9a865a99e50afb79034e1ea29c30726/34021458112.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/3ad9gdm16v42clplimhmvcep4o/9244742787.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1e4deb560---pilifuwumoragezo.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/1abf48dbf7dd3776e4e31d8120df9aa1/mekur.pdf
    • https://easybuildapp.com/files/uploaded/files/86824997126.pdf
    • https://brianhigbielaw.com/UserFiles/file/moputeta.pdf
    • http://albatrossmrn.com/konadnew/userfiles/file/wumejawipak.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/3q5h4basu8lbno6ba55fv9naf4/womibebezosusifixo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=500+to+1000+words+how+many+pages
    • 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_off0000ebb4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB4 16792 bytes
font_01_sfnt_off000103c6.bin
2d5b5887d2d69d8dc04d5e063f269f749f231847fae796323e0b1050ce8c9f4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x103C6 18872 bytes
font_02_sfnt_off00013283.bin
a0c99aa4f36ef50817631d92f4d00ad60e05ebb76e579158ac9784404f28cf23
pdf-font-stream PDF embedded font (sfnt) at offset 0x13283 11112 bytes