Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85870177801a8db…

MALICIOUS

PDF

83.6 KB Created: 2021-07-01 23:31:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a8ed29709dcf8b167dc16c76704b96ec SHA-1: 4933ec2a54ceff832c8dc8186140449bbcc41ae4 SHA-256: d85870177801a8db6eb7332d45cf6599d8d759ea81cadf97107bc105a9b706ed
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics suggest it functions as a link farm, with many URLs pointing to compromised CMS uploads, and it uses an invoice or payment lure to trick users. While no scripts were extracted, the presence of numerous external links, some hosted on potentially compromised sites, suggests the document is designed to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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 http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3ed32f573---76645407340.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/e795b22e6b7fc98b616ffa389d90a53b/74539753043.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9fb0bbf962---64129270305.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071d11a33b15---56625277117.pdf
    • https://alshaabcoop.com/userfiles/file/30155411145.pdf
    • https://moto-trend.cz/public/files/fck/file/46238253358.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/93b992ef376a7fb3cfb08c5de60aa360/negonawokelos.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a7011ca1b---3207871592.pdf
    • http://everest-c.ru/ckfinder/userfiles/files/10137687080.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad2b66cf7a5---paxolalolitaxabavogos.pdf
    • https://clubslotalmatriche.com/calcas/file/78811750237.pdf
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/de17ebec62eab1431dc20f450e8666e3/26801958726.pdf
    • https://galerie-louise.be/userfiles/files/976055936.pdf
    • http://martonaroniskola.net/userfiles/file/83395849086.pdf
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b24daa2b32---19889946725.pdf
    • https://e-uchebnici.com/img/file/luzijimovo.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/bea471e890706e63e4df0afc75610436/lenudurexobutu.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4c76440e7---japavisujoxuvakeke.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/8a5pvh65fi6tn7pju9mtjc23or/rovixudebozoxip.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160abfa2b8ff96---22166863703.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/e1ad0b1a2c635daf3c846c2625558954/metopaxolebedaxepa.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d55269e1e70---40125433338.pdf
    • http://abacusnancy.com/userfiles/file/13286888169.pdf
    • http://i-daa-wl.de/userfiles/zavuzigivuj.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=preparation+and+analysis+of+financial+statements
    • 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_off0000e542.bin
551bf92dc2100f8e289cf86850651c86f9cd7297732c78d2a3eaec9928d2173c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE542 16212 bytes
font_01_sfnt_off00010f31.bin
c748a782177c45074978a4c07f7d4ac9145698e27620f32d25149f9cbaf361ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F31 10896 bytes
font_02_sfnt_off00012867.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12867 16792 bytes