Malicious PDF — malware analysis report

Static analysis result for SHA-256 38ede0c849208030…

MALICIOUS

PDF

70.0 KB Created: 2021-09-24 13:17:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4954208769e65733f01f07b307246cb8 SHA-1: d8be529278e54274f638ec7f01f4e0c25e0527b8 SHA-256: 38ede0c849208030a49158ffcb46d2400d0689ad94d630b9c87f9f5dd4f6b678
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing lure. It contains numerous links to external PDF files hosted on various domains, many of which appear to be part of a link farm on disposable hosting, suggesting an attempt to distribute further malicious content or phish for information. The presence of embedded URLs and the heuristic 'PDF_RANDOM_URL_LINK' indicate a strong intent to redirect users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 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.
  • 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://wastran.ru/uplcv?utm_term=android+system+webview+download+apk PDF link annotation
    • https://sthouseluxury.com/upload/files/2410248201.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/37835267807.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/rukenox.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5d53f1db2---88028556088.pdfIn PDF document text
    • https://777mto.info/contents/files/70546212472.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/12311868565.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/fujumukirulufulizazununuj.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210923_185542.pdfIn PDF document text
    • http://letsfinal.com/userfiles/file/96629661178.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/retagebopu.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/66e44dc6dd6ae6fd3be31f2ab693347e/23565992065.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/8384890517.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/xawisadixanazoxavagaz.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/31687780631.pdfIn PDF document text
    • http://honeystraw.com/uploadfiles/file/povow.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/wodoxaboxukenenekuzifu.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/67360841001.pdfIn PDF document text
    • https://hefcom-hydraulics.com/ckfinder/userfiles/files/56394759629.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/sexabizafuf.pdfIn PDF document text
    • https://kvizek.excore.hu/ckfinder/userfiles/files/37779222122.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/sevabalena.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/ranuloporega.pdfIn PDF document text
    • http://weddingdove.tw/uploads/files/202109040315072210.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_off0000af9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF9C 16216 bytes
SHA-256: 37f8f4ec55ef0b6470295375a60026bf0d4145eaf1509904dbcc3e8b8a2ed826
font_01_sfnt_off0000d8c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C2 11032 bytes
SHA-256: 9924e8bef6e0ec225681e2d57428deaa7822c62bc3ba47b6c3608959ac54a8e0
font_02_sfnt_off0000f24c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF24C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1