Malicious PDF — malware analysis report

Static analysis result for SHA-256 4365157bda4e7f49…

MALICIOUS

PDF

67.7 KB Created: 2021-10-04 03:28:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a23dcd648ccafe05e9d6da1b34bb760 SHA-1: 771c2a2376f6f2728fb88c586bd9af1d4bd93d53 SHA-256: 4365157bda4e7f491da56335dafa183f58071a60a3b1d5d32358e60d89334d45
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV, indicating a phishing or malware distribution attempt. The document contains a link farm with numerous URLs, many of which point to potentially compromised websites or disposable hosting, designed to redirect users to malicious content. The presence of external URIs and link farm characteristics strongly suggests an attempt to lure victims to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://tuzvedo.hu/elemek/file/mawenujamebe.pdf
    • http://thunderstar.cn/userfiles/file/20210914111237320799387.pdf
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/tutejifapusena.pdf
    • http://ersenergy.com/UserFiles/file/jaduga.pdf
    • https://samsungdvmklima.com/upload/ckfinder/files/vufukomidogitan.pdf
    • http://wittymall.com/multimedia/userfiles/file/26784266809.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/lslhsif6s183mf1mhugej20f95/6334612.pdf
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d05816915---kanepigusurugibuberuga.pdf
    • https://laatuwhuisweerstralen.nl/upload/file/31541622842.pdf
    • http://haliburtonhighlandsheritage.ca/userfiles/file/1080089906.pdf
    • http://form4concrete.ru/pics/cont/file/63417245461.pdf
    • http://faptvmedia.com/userfiles/file/45190678971.pdf
    • http://5percent-design-action.com/upload/users/files/jeteru.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139be56a22ff---92825108314.pdf
    • http://perchegouet.com/ckfinder/userfiles/files/81486996908.pdf
    • https://woft-dining.com/webroot/editor-uploads/files/60944062212.pdf
    • https://veaodaibrahma.com/uploads/image/files/8152203934.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1615704868b0be---4206941471.pdf
    • http://deshdunya.com/blogimage/file/2723486732.pdf
    • http://avatars.ru/userfiles/file/51460423432.pdf
    • http://bibliotekaszamocin.pl/img/upload/files/39773404515.pdf
    • http://globomax.eu/userfiles/file/49534049566.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=better+words+for+because
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ad4f.bin
3da1af1db49a28440a805b7021a3d4ab1adf21f0d51469aaf7102bcea9cce7be
pdf-font-stream PDF embedded font (sfnt) at offset 0xAD4F 10604 bytes
font_01_sfnt_off0000c5d3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5D3 16792 bytes
font_02_sfnt_off0000dde5.bin
6a78cad7c2668c6bd4eb99543805741b09a115f04a2fa68e6e70a5aa6408c996
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDE5 14324 bytes