Malicious PDF — malware analysis report

Static analysis result for SHA-256 ddb6b31804259f56…

MALICIOUS

PDF

89.1 KB Created: 2021-08-25 09:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dd8986ea3ca20623caf439d89c93aad3 SHA-1: 6f963bc5b8467dc166bbb7e04875f17fb256e36e SHA-256: ddb6b31804259f560dfae6878bd58356e687dc074cb188da6ad42fd6be838a90
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://auf.vn/wp-content/plugins/super-forms/uploads/php/files/o7bufsuco3dppm7o926it8mpr2/falunodimiwulevuk.pdf In PDF document text
    • http://anhuifan.com/upload_fck/file/2021-6-3/20210603103135907385.pdfIn PDF document text
    • http://mhinflatable.com/upload/file/21168636414.pdfIn PDF document text
    • http://nofatrans-int.com/userfiles/file/70060681072.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160711c90a2c25---vukemodakofesobikive.pdfIn PDF document text
    • http://blgjad.com/upload/files/neganodifadip.pdfIn PDF document text
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/25227476247.pdfIn PDF document text
    • http://yeditepegumruk.com/userfiles/rejolimakarororigesuke.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/e701ba2d92b809952ec7902df0d9e639/27112928529.pdfIn PDF document text
    • http://dentherapia.hu/files/file/titegutilefim.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/eba7f2cd1d519403d8c06c221d40da59/46797929210.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/xokakezajinuxedibupi.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/76094849511.pdfIn PDF document text
    • http://atrsara.ir/resource/files/welidevadamowunowogapopu.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/1e38064dbeb56c0cabdbf9e798f991cc/guvekazikiramabaletelafar.pdfIn PDF document text
    • https://medius.sk/userfiles/file/79917621711.pdfIn PDF document text
    • https://www.sterlingsez.com/ckfinder/userfiles/files/9167555400.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/2118745276611b2531e99ae.pdfIn PDF document text
    • http://blissworldbeauty.com/newerac2c/userfiles/file/81379351631.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2a6e73a40e---tuxexajipegoj.pdfIn PDF document text
    • https://eurotig.ro/file/4614404409.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160905260908fc---zexugazojid.pdfIn PDF document text
    • https://www.idd.no/ckfinder/userfiles/files/26202302461.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/xuvavutatibula.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=materials+engineering+science+processing+and+design+solution+manualPDF link annotation
    • 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_off0000f733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF733 17344 bytes
SHA-256: ec0e3a7226c9986a8f448d69b98410f4dc48229b56f576b546c59f1e63d61e18
font_01_sfnt_off0001249a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1249A 10952 bytes
SHA-256: 87d888056251a7334dff1ca24b83dc3401b71517a2a88b7d30cbb1f1e869f7e8
font_02_sfnt_off00013dc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1