Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ef39658c6ee1d20…

MALICIOUS

PDF

70.1 KB Created: 2021-09-16 20:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3cda37f1da4ab814b439b074e1950b5b SHA-1: ae0a0b16b48c3ad9b90c5c781c5acc1b08b519db SHA-256: 2ef39658c6ee1d2074df478d304e3738fe0200d706a953b77a9816a7201c0d14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or link farms on disposable hosting, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of a spearphishing attachment used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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 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://smidgel.ru/uplcv?utm_term=signal+strength+android+app PDF link annotation
    • http://pepinieres-soupe.com/userfiles/file/wifovexafugen.pdfIn PDF document text
    • http://www.ferm-matic.fr/upload/file/dugug.pdfIn PDF document text
    • http://quangphong.vn/uploads/image/files/37057612758.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/3b7e466bb40527626932815f764a1ce9/wojituga.pdfIn PDF document text
    • https://www.dooleysnaturalgas.com/ckfinder/userfiles/files/faguju.pdfIn PDF document text
    • http://www.ccengis.be/applications/ckeditor/addons/ckeditor/ckfinder/userfiles/files/78386020719.pdfIn PDF document text
    • http://land89.com/ckupload/files/piwebubufefivigevopi.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614057c932a09---jiropikawa.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/wasuwupalizabetugosit.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/8kvllempe8ir4mjsd16cu0s3b2/65010644909.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/33482929924.pdfIn PDF document text
    • https://tch.lu/files/files/38131828980.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/lupajebemivoposokegera.pdfIn PDF document text
    • http://tznjl.com/userfiles/files/20666582644.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/27c7880a85a57c65951f52cf96417197/14525220420.pdfIn PDF document text
    • https://znalac.com/userfiles/file/23692325537.pdfIn PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/97310147862.pdfIn PDF document text
    • http://gddfboiler.com/uploads/files/vujopi.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/12832400553.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/52423131529.pdfIn PDF document text
    • http://alisawedding.com/upload/users/files/80433573000.pdfIn PDF document text
    • http://nanopena.cz/upload/file/45495351951.pdfIn PDF document text
    • http://pileki.com/imgup/file/javelidaka.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_off0000b211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB211 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA28 10748 bytes
SHA-256: e0733926bd86f1568a5f3696be3679db34ed01470834de836211fbb36f9b6cf3
font_02_sfnt_off0000e28a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE28A 15888 bytes
SHA-256: ad9896078a9d7c30be6983baf5bf07ede18a2b2159bf7cc1fa4987002808cdd1