Malicious PDF — malware analysis report

Static analysis result for SHA-256 678ceaef0fd1f7d0…

MALICIOUS

PDF

81.5 KB Created: 2021-07-29 17:51:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e2d551a23e0caac48c6ea05eeef03647 SHA-1: 6a6fb76797e24ef6e8ec12730a57c988c6aab942 SHA-256: 678ceaef0fd1f7d0f81eb3ddfe43dc19faafdaae3a882f0dad510193034619d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to compromised CMS upload directories, indicating it's designed to host and distribute malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The document's structure as a link farm points towards an attempt to lure users to external, potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 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://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160926ac4175d8---84471502701.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/da1d01501ce43f79e5231315cfd65380/dumesavetarojupelukuxor.pdf
    • http://autoscuolauniversale.it/userfiles/files/xufosilaxukinipufebe.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16099d05c80b0d---roroxemivavaxaxilade.pdf
    • http://fsnmmaterials.com/UPFILE/userfiles/files/jakarelavibir.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/c51abohtis03s4dn01d8t3gm4d/44849999678.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/01d559730d5f93ede118d6201ba2587e/kisuzujopuxilakiruwapute.pdf
    • http://cesnek-vysocina.cz/UserFiles/File/lugulifenazokabeka.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16091920385da7---xojukig.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/6d8468183ad35f90a546418b7af9f0ca/92263679536.pdf
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/dhrgl5lmjq9i9peadahva1ijlb/kufomaduzak.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607bff3d0aaa8---61710628012.pdf
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/af460fa0d7494cda3b64b490ffafb3bc/wefinukifevuge.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cae7402a132---52327266686.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea70325fea---56244544198.pdf
    • https://mkycc4.com/kycc4.com/userfiles/files/96580895038.pdf
    • http://zae.me/datafiles/file/3249661937.pdf
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/d2aff2af316a4757fcc8f1bc59692678/78375240157.pdf
    • http://praguetransfer.com/files/file/kedoraf.pdf
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082cc8e93391---45404687714.pdf
    • http://moreit.ch/productinfo/file/54642245497.pdf
    • http://standdominica.org/files/files/78077057191.pdf
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/ae11b3c2fb410ca0ca55d642f5c8733f/35372605679.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=difference+of+two+squares+worksheet+gcse
    • 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_off0000d8d3.bin
3546ca173209812af3f834c6f461b59512c1ba91a26cd11294fc358456b45695
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D3 10992 bytes
font_01_sfnt_off0000f226.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF226 16792 bytes
font_02_sfnt_off00010a38.bin
62f94b2f2b1fd12c1e4ca84da1498e5146c0e6bb5873ef7651e36b4301a50db3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A38 17464 bytes