Malicious PDF — malware analysis report

Static analysis result for SHA-256 504c7bd2d4c4cd76…

MALICIOUS

PDF

85.1 KB Created: 2021-06-28 21:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c0db29687f3f302df764875b86a7471 SHA-1: 8bd838a6bf2767b2afde2106cecaceea0eaf76ea SHA-256: 504c7bd2d4c4cd76f8c10c778ae4b79bb94515ff56ed5c1de0b7048aaa382c39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=ankle+and+foot+doctor+near+me
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/96b59eccc89f05a2dcc81a2a35ae3303/46640585451.pdf
    • https://prospr.fr/ckfinder/userfiles/files/25497586270.pdf
    • https://cvsc.co/userfiles/file/91962411133.pdf
    • http://soupworld.de/upload/file/26942483978.pdf
    • http://broadmoor80.com/clients/866172/File/xemulub.pdf
    • https://kudamatsu.org/userfiles/file/25219022030.pdf
    • http://adamlegal.com/userfiles/file/resadixeliwinodajenexovos.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c24e0f41612---37997404065.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098646183e2f---66955013373.pdf
    • https://travelsafeway.com/userfiles/file/soxofatikebegorumowudaruj.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a2ec022087d---55679804027.pdf
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f24d5af084ab8ec6f74fc4e36212c012/tevejiwupubiw.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/3792c05965ca2fc8e6e1fc326ff39474/vutusuxerotogesi.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094c5d036fa8---11461673715.pdf
    • http://hanhthien.net/uploads/file/5874112055.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/a9ih5jkf5nf9fppn9h2gsb4tcp/sifatipiwonuxab.pdf
    • https://aprilboya.com/userfiles/file/vofiduzilinilibupu.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a707aa84598---94055734862.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/63951490b1f1c6b58cf57c59f83220fa/73816142526.pdf
    • https://palcev.ru/userfiles/file/59091701033.pdf
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e1697504a---88449083350.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce2c330a87---40961626218.pdf
    • http://cambresisemploi.fr/ckfinder/userfiles/files/xitusufivufogoruzexa.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160787db359255---gobumofumoga.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/cbmiuekprn5d429pjqc9tu5cm4/xesimutexokuk.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/ones40snkcd9scpjv93u72k7u3/pevisabisogetif.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_off0000eaa1.bin
22e06bcecbc26c124f87954ec5162c0619912f417d60e155ea3dcb1b18fbe667
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA1 10448 bytes
font_01_sfnt_off00010261.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10261 16792 bytes
font_02_sfnt_off00011a73.bin
9f170adbe2448c28af9fbcefb7f3c4c6998e756d5ba293a89f5c3c43b4aa08d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A73 16980 bytes