Malicious PDF — malware analysis report

Static analysis result for SHA-256 1deb80c9843f5af4…

MALICIOUS

PDF

67.9 KB Created: 2021-06-07 05:56:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 3eb26544664466c5e5f22d25a738a04c SHA-1: 4dd6823791b9d200c914689ce4248addfca3800c SHA-256: 1deb80c9843f5af4419579710c1fbfb644be29827b573d6643bf16e2a517c3d6
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF document exhibits characteristics of a callback phishing or tech-support scam, as indicated by the 'SE_CALLBACK_LURE' heuristic. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting an attempt to host malicious content or redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving exploitation of PDF vulnerabilities to deliver a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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=equifax+dispute+letter+form PDF link annotation
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5bf25ff73---91801465195.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a5ba05d26---27717781617.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160722ca1be24a---47843395272.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a238735b1a3---3186163159.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/f603038788076a5d442c3625ee7ff5f3/kimebizaluxugutotive.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985a62ecc21---juvikaxitodinozofup.pdfIn PDF document text
    • https://p99.tw/pro_pic/files/tizutexit.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a68d5cea5c2---29812729719.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/76de0134a0f2359add105fea6f4cd069/11110913402.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/96817058342.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/nqbf408cmvfu9r9ft4ot3dsa13/tatovugifo.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160739a3560cf9---xoxisefikokixiwokolot.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16090f4f18a051---50551931969.pdfIn PDF document text
    • https://cahayaapi1.com/contents//files/43181277178.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cdb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB0 5340 bytes
SHA-256: d061c29c9b732c2e6cbf577effb7668693b7777113e844ec52947f1349ca38cc
font_01_sfnt_off0000dfcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFCB 10340 bytes
SHA-256: 382662d9eb450f29164ab7c71381de61de1691244ff869648907c1414bbeda8c