Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ba7e27fe843e81e…

MALICIOUS

PDF

94.5 KB Created: 2021-06-29 06:01:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: cac999e6921217f3908de401ebb02daa SHA-1: 5469cbb584d029bfb8dcba96406bd89187ad6ee5 SHA-256: 4ba7e27fe843e81e1a3d2581484f5c1d7193105896b0737de282181dd08cf105
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the nature of the link farm and the PDF structure points towards an attempt to exploit users via external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://coretry.ru/uplcv?utm_term=homemade+applesauce+without+sugar PDF link annotation
    • http://grafiport.com/userfiles/file/264213556.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/81d40d7168498cb0381dc8fc9281d664/75202359100.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaff31539a9---jerulim.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/96299fa7c03c0ddd678d3fb2d12c2bc9/ketukerekuganam.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/88916998792.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/99588144419.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/8ic54cojrsk8uj8ms49bphpovp/bodok.pdfIn PDF document text
    • http://esistore.be/userfiles/file/4652838403.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/rlhtj7gouf0d2hpif6t0p03ne0/40282726370.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/zodokuv.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/cd7f786e722cfebebbd5a1df9837be9a/ganibenokonetefuseves.pdfIn PDF document text
    • https://vestol.bg/files/file/lovigovu.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089f728b6365---dipef.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b6fba45ae1d---sedafativovede.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a856b5de9f8---namexujufo.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070582b4a5cf---titanejuguduwileme.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/falefiwu.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ad11bc005b3---terefuxolut.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/98461173103.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210628_165230_9683.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160860ff7eb326---28443951409.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/38d68f04a143ff4e8a33c522150db951/93659648848.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160aa24ae532f1---3610196740.pdfIn PDF document text
    • https://istanajpdua.com/contents//files/bazuzukufa.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f41a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF41A 11032 bytes
SHA-256: d1ff97cdec398a462da4f33f3a8bef573e57f1ff8f93256030d2dbbccaf77ca2
font_01_sfnt_off00010d95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A7 18064 bytes
SHA-256: d6985a19416ffd5145adc8b9f6d330e2d600e24dbcb13b395c79f822949085ee
font_03_sfnt_off000154e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154E2 16224 bytes
SHA-256: d6dd8f09a97dbabc13652295f0acfdfb2300323efe6c6ce91bb145bb9206f541