Malicious PDF — malware analysis report

Static analysis result for SHA-256 1811a6a4ef042f58…

MALICIOUS

PDF

81.9 KB Created: 2021-09-05 15:37:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9ba5dc177909614a5554c68ae769ec34 SHA-1: 4a8c4b48a8c6564b32fec14ad16f75254a2c0633 SHA-256: 1811a6a4ef042f588dba0c84ee302cbb26279e673d320cc7aa0432a7d861ec2a
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content or phishing pages. The presence of these links and the overall structure strongly indicate a phishing or SEO manipulation attack.

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://medvor.ru/uplcv?utm_term=rotate+pdf+and+save+adobe+reader PDF link annotation
    • http://afghansolar.com/userfiles/file/folugekiji.pdfIn PDF document text
    • https://kuraniterbiye.com/resimler/files/55620688829.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/rovozadixomunaju.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/bazelopulimemodifosumaj.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2aa4686655---rudimutepeziwinuvotis.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/cd0d2e5d830c89ec65b255a9d1bfd6eb/99322624546.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/451b1cc22faee3d32523d2ff4a20ec0d/474259348.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/31343331270.pdfIn PDF document text
    • http://zerosquareonline.com/file/46525267838.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160740f825e701---56828015740.pdfIn PDF document text
    • http://skomi.ru/img/files/file/29574387282.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160fd672445ee0---wulowigimakigiz.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/pigavalegumefetuzitoso.pdfIn PDF document text
    • https://trunglamdecor.com/uploads/userfiles/file/80919335623.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/cn52j0vtm7l3kqleudqnglb6d5/ragunetosafevipipof.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/10998384457.pdfIn PDF document text
    • https://rusepress.com/uploads/wysiwyg/files/71005624770.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/cos9b06rc5fsevqipim7p8b6fk/wolugogolarilujezuvata.pdfIn PDF document text
    • http://radio6deenero.com/uploaded/files/47672736072.pdfIn PDF document text
    • http://weddingdiy.cc/uploadfiles/files/20210602_212752_2693.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/92530f019ba4df8623ad16e25e537794/7892309891.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202108230837215612.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/7935630236.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_off0000da34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA34 18308 bytes
SHA-256: 6d9f6402376a9f09eff177dbfbb6c4081900041f1cce0d8597587da466ecb59c
font_01_sfnt_off00010990.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10990 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A7 10604 bytes
SHA-256: 4373fcab9392c3261e085d483cd67636d9a4c24bcdda1c244e019fc221f5f6ae