Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec08a8523818eec0…

MALICIOUS

PDF

84.5 KB Created: 2021-08-23 17:16:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 6ef1a09259701a4e7b5c9ffcc1738c9b SHA-1: 8adda151a532d7650e74d27902192f05e5b56302 SHA-256: ec08a8523818eec0e3cc841361331e0e62d179e55743384dd50670e3aee88c38
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or domains associated with link farms. The ML classifier strongly indicates maliciousness, and the heuristics suggest the document is designed to redirect users to potentially harmful content. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document intended to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • 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://laborke.ru/uplcv?utm_term=find+the+equation+of+a+line+using+point+slope+form+calculator PDF link annotation
    • https://barcelona-health.com/files/galeria/files/16296416891.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/17294550317.pdfIn PDF document text
    • https://soalmatematik.com/userfiles/file/maniko.pdfIn PDF document text
    • https://artlabjo.com/userfiles/file/37417217098.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/42f209b30f9d57ba3e5226bb939d93a6/patub.pdfIn PDF document text
    • http://cuanhuadanang.vn/uploads/image/files/bisulokabave.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610b453905e97---xawiwobaxokomuti.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607000a501449---vegubufudiwopanetalolepul.pdfIn PDF document text
    • http://kientrucnhacuagio.com/upload/files/78366463274.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/20771059731.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba26dcb8902---kixilamibutone.pdfIn PDF document text
    • https://brune-schmuckwerk.de/ckfinder/userfiles/files/fubobabugoj.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/mezuvapiro.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/49604092586.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc3669213a---94370004052.pdfIn PDF document text
    • http://omni-links.com/images/blog//file/wixulasesuxikorebexepiral.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/mazakuvubiwasizidegitab.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/tenusotar.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/596e2903822001fef9a0d1e6f93d2741/lefipelopimez.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/21337792431.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/18284085723.pdfIn PDF document text
    • https://www.privathospitaletkollund.com/ckfinder/userfiles/files/roseroripirasix.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/gofuladejovemogud.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609815facb585---ximesagibuvejuxizabek.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160856e10be8fa---norovobase.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_off0000e19e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE19E 17928 bytes
SHA-256: 0bbffa80f6e4ab252135995ec0125020bc4b865dc15d87e486171b491e62e550
font_01_sfnt_off000110b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128CA 11288 bytes
SHA-256: 55253d7fdb1a4a776c6d0c7f31d964b4e1cf52b5c399da49150e98aa83d64f42