Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc8498ef4d976e86…

MALICIOUS

PDF

81.1 KB Created: 2021-09-12 09:59:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3b0a8b80e36c0ba125cdfacba5f90874 SHA-1: d63aea6c2b873dd699a10510fb868db0f300e483 SHA-256: fc8498ef4d976e86aeac30f1646ddcce8e89d4c6813f6ca6c7ce5c6ae4a9366d
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to disposable hosting and compromised CMS uploads, a common tactic for phishing or distributing malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs and link farm structure suggest the primary goal is to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://inwebjor.ru/uplcv?utm_term=boldbeast+call+recorder+pro+apk+free+download PDF link annotation
    • http://theponghop.com/upload/files/nafafigelopepenaneguned.pdfIn PDF document text
    • https://denimder.org/resimler/files/vujafameniradozato.pdfIn PDF document text
    • http://canadapremiumlubes.com/survey/userfiles/files/31977489141.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/rumosilukoviju.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1613886e71c34d---komebawutugesexogurafi.pdfIn PDF document text
    • http://tiyuchangdi.com/upload_files/files/20210905_222009.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/filikikitizudefagip.pdfIn PDF document text
    • http://columb-sklep.pl/userfiles/file/rodefotofutupibisu.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/c5077a8d234da418d3c95c994e872578/59589684698.pdfIn PDF document text
    • http://saigonford3s.com/uploads/2021-09-10/images/files/duxagojigokikuk.pdfIn PDF document text
    • http://parfumland.sk/upl/40584450993.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/47316385108.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/gafewamex.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/66682018791.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/2234897491.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/71481728663.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/89143861761.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/kinovamej.pdfIn PDF document text
    • http://ilonew.tasksplan.com/ckfinder/userfiles/files/71543539067.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/lpk3fjdkq7vmb87j0oar7ojisu/mezel.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/68876314480.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/ripezofimubejarotewogox.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161325bbfc4738---51513757604.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_off0000d50e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD50E 18468 bytes
SHA-256: e50b715507bb50cae9808c4aeb4ccf71378668267cdd34861122edd4149a3c24
font_01_sfnt_off00010521.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10521 10892 bytes
SHA-256: 34ef4588b6b3b7936ea2dc749b40e715066a83f4f6ce950fa5586740ac9be920
font_02_sfnt_off00011e5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1