Malicious PDF — malware analysis report

Static analysis result for SHA-256 d855e889245e17f2…

MALICIOUS

PDF

77.6 KB Created: 2021-06-26 13:44:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 063bc325ffc394393821cbc5ed2324b7 SHA-1: a31d8efd2361c55cfe0ab0d8339f6604e02005c7 SHA-256: d855e889245e17f2acf8d35acde4cec26b47d5c46912e3f67a81d9dad02a4ac7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to compromised WordPress upload directories, which in turn host other PDF files. The presence of multiple distinct hosts and the use of 'utm_term' in one URL suggest a phishing or malware distribution campaign. No scripts were extracted, but the overall structure indicates a malicious intent to redirect users to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a28ec314b9d---lupilomuzajozarobebunojet.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/9847e310d86c9a860f9981c5fc1c88ad/3661879134.pdf
    • https://calmoinc.com/upload/editor/file/regipazevijinifukax.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ce9b71187---51208470656.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/265536183f1ac9b3c87b175bc1ce9103/kosukulufopu.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/tloqr1eah6pp479uv5hn5r6l6o/rutojoruwejigijetoda.pdf
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/178c8202bf523b911a9341d8ab35c469/zadogakipu.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/v89u9p7vclu2kk5trh4c7bis36/gejoxelubiwuwitug.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/5e781fd95ebaaaf328c0ecb6a288f1b5/87022072209.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e87bcad5f---bumejupozevebudavirevu.pdf
    • https://nanyangtextile.com/userfiles/file/jukojiwejazosavasekexikiv.pdf
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2256a4e0d---pesotezanuziwesikefeniwe.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/025r6efq3ivrak42o02ikfnoe4/85778436009.pdf
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/58955394540d9cc67dcfd8dd5baec93d/gaxudekesevizaxapoduwe.pdf
    • http://firmykominkowe.pl/Obrazki/edytor/file/govozesibevemaposunade.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ce9539afe2e---fuzazusa.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/l41jct8afna9qpmarecogl32ks/maredafowuduz.pdf
    • http://archi1919.com/smlclub-files/file/22594990584.pdf
    • http://win-sonic.com/kida2018/ck_imgs/files/61017372180.pdf
    • https://noihoithanhtuan.com/media/ftp/file/rilogorupanadu.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/16095bff3e414e---60959175147.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb6830412e---80102225384.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160877059e4948---69805808450.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=how+many+ounces+of+water+make+a+cup
    • 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_off0000cbb5.bin
14447ac0baa1c246eb7d2d7830f18bf184c67e0a2dcea3b638ab202aa2eaef53
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB5 10888 bytes
font_01_sfnt_off0000e4ff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FF 16792 bytes
font_02_sfnt_off0000fd11.bin
b4846d05a8edf38ec546d6048a4185844552695f75a310257bde8add76dc5faa
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD11 16764 bytes