Malicious PDF — malware analysis report

Static analysis result for SHA-256 71e98f40affec187…

MALICIOUS

PDF

95.0 KB Created: 2021-07-06 18:51:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 39fe7647a5ee646a1a0be4576f8c56cd SHA-1: 52c0070aac68f88ea21e6afb36f1e235c6c1ea38 SHA-256: 71e98f40affec187a63e6979465854690611a9e0a5a1d78bc8cd542d44435a2c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. The file's structure and URL patterns are consistent with a link farm designed to obscure the ultimate destination and leverage potentially compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://anhuishangbiao.com/upload_fck/file/2021-5-5/20210505155902448730.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0267349b3---99774410572.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac69b858fa---8131453271.pdf
    • https://maintogelonline2.org/contents//files/50088727107.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16072b8bf88004---14403897043.pdf
    • https://henklinders.nl/henklinders/upload/files/davuvukov.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/16070db3de3af0---gafupolal.pdf
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3415efd35---8523887223.pdf
    • http://chapelguild.com/images/usr/jufifelilapimogaxaga.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/88afc59fae631d838ebae9d149ceaacb/32483041364.pdf
    • http://forter.vn/hinhanh/file/vamaxagewivasasunigazile.pdf
    • http://mtsskzy.com/userfiles/file/17933236294.pdf
    • http://xboxheerlen.nl/userfiles/file/24037418262.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/ilke6mfhahsvfror86qicmptvv/45438475896.pdf
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/kobefepedanakikixikopufex.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/8d2248c13bccfce166975870486cd336/tinosurukuvig.pdf
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/9c125d7d75933e23cdaf414e1d6633fe/zetosezaziwidifozud.pdf
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/59ec3841fcbdec6956ff8f09290f77a4/28302899643.pdf
    • https://aadhaarretail.com/administrator/imagetemp/file/kemuzekotezufe.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=the+battle+wizard
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/b48998c9612e4c60587304cb5f3e47ec/4263432279.pdf
    • 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_off00011345.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11345 16792 bytes
font_01_sfnt_off00012b5c.bin
61701c8e6674712ad43c560c4bdd6e25e041f3fde4f72963c39468050b152316
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B5C 10204 bytes
font_02_sfnt_off00014268.bin
2f606757e2627be4e500c1b05216934188f17e6dd2acbbe659b5ec26e3662bb8
pdf-font-stream PDF embedded font (sfnt) at offset 0x14268 17112 bytes