Malicious PDF — malware analysis report

Static analysis result for SHA-256 c78b3ede4e0f3f92…

MALICIOUS

PDF

109.6 KB Created: 2021-09-05 19:34:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 39b9f3bb60c0c097c3fc9d707a6d36f7 SHA-1: 22c71d9b7c29cda2f0aebd46c3f85b41734a63b4 SHA-256: c78b3ede4e0f3f92f8f38fcbe028f5e4a5d19a530170ebb2dee38be323969f92
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV both flagged this PDF as malicious, with ClamAV identifying it as a phishing trojan. Heuristics indicate the PDF functions as a link farm, containing numerous external URIs pointing to various websites, some of which are hosted on compromised CMS uploads or disposable domains. This suggests the primary intent is to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://bookatowncar.com/userfiles/file/72877518418.pdf In PDF document text
    • http://paolacaone.eu/userfiles/files/gomidilukexufiduzojirufe.pdfIn PDF document text
    • http://1970fchs50thclassreunion.com/clients/1/19/19770213778af891f1b13fa25f964f50/File/woxopavepebevelazepe.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/kifipidu.pdfIn PDF document text
    • http://szm.hu/userfiles/file/5167482223.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/lotovaduzop.pdfIn PDF document text
    • https://mauspro.net/upload/files/vikuzud.pdfIn PDF document text
    • https://fasaac.org/temp/files/31895189960.pdfIn PDF document text
    • http://proxima-design.cz/files/file/rakowikanitukozase.pdfIn PDF document text
    • http://cpk.by/ckfinder/userfiles/files/84407685506.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f137e68cc1---9031831731.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210702031808.pdfIn PDF document text
    • https://rijst.nu/userfiles/file/68296257671.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/30926043710.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160964c3672660---48055202669.pdfIn PDF document text
    • http://fapannimario.it/userfiles/files/23733572616.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/riwevolepezezabirak.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/29841124464.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160985ad813bf4---betifabixo.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/9840dcbbf49a84980274a4e183b0766f/2256544534.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/db85aa2db9721d33013c6db3f0aa037f/wopowuvomigoliwopo.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/42174350213.pdfIn PDF document text
    • http://contrast.no/ckfinder/userfiles/files/vagogojotumizolifoze.pdfIn PDF document text
    • http://microsolder.hu/userfiles/files/gepebefumob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=insulin+degludec+davis+pdfPDF link annotation
    • 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_off00014e30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E30 19132 bytes
SHA-256: 8f60289f4510f08e769947f6d4c24de0437efacc2ff0c62b117901f822804625
font_01_sfnt_off00017fe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17FE3 10596 bytes
SHA-256: 085a78edb17c2fe1c2fbdc41c7050304a86b8c551b55e11cd0eff8236894980f
font_02_sfnt_off000197f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x197F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1