Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fd17df06f5ac842…

MALICIOUS

PDF

74.2 KB Created: 2021-09-11 08:44:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 17aa0b52f2bc300a7ca2471ef733e14c SHA-1: 889d4dd1c8c51d6158ca38929453dadecaf1f541 SHA-256: 7fd17df06f5ac842a77fb2c9df6a195843ab29066a26f146eeff2b424e2e8f70
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised websites and disposable domains, likely intended to lure users into downloading further malware or engaging in phishing activities. The presence of external URIs and link farms on compromised CMS uploads strongly suggests a malicious intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://synerhu.ru/uplcv?utm_term=irctc+apk+download+for+pc PDF link annotation
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0800e2abb---denipizuje.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132807c611c0---jokaluvewakajuboga.pdfIn PDF document text
    • http://neoneophytou.com/ckfinder/userfiles/files/58052086457.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16130b3537e23d---20450622859.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/kusowafufuniv.pdfIn PDF document text
    • http://charontrade.hu/data/file/95860717769.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/98704681113.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/dezolalukiragamu.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/1au9nf6asrmlqcl3ig19ln362c/nolifosopev.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138c79c81445---vipedapuz.pdfIn PDF document text
    • http://szhlfz.net/upload/9044029063.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/c46dfb9345eed5034721b008fdfda41b/lobosifusiwexofegelajofum.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/16479956663.pdfIn PDF document text
    • http://fmmvn.net/userfiles/files/74900365150.pdfIn PDF document text
    • http://perilatomsk.ru/ckfinder/userfiles/files/dipuxefinodapelumij.pdfIn PDF document text
    • http://bora.su/ckfinder/userfiles/files/nasuxo.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/josokegetanuto.pdfIn PDF document text
    • https://xn--80aggmy8c6c.net/UserFiles/File/sovatet.pdfIn PDF document text
    • http://rts-3.ru/upload/files/tiwutop.pdfIn PDF document text
    • https://sooryasales.com/uploads/file/pujulosepobuzimepefi.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/63108740641.pdfIn PDF document text
    • http://sbsinternationalschool.org/userfiles/file/57921203719.pdfIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c01a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC01A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD831 10348 bytes
SHA-256: 93390e848462e38bc10f7d0d28bf0ed9e7c323db275c0eff38455b37a3a3b490
font_02_sfnt_off0000efbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBB 16692 bytes
SHA-256: cbbcd1440d67ba36f2d0ef93d89509a8d132492a2d12d64ab059211eb117c607