Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4c9c6a724165a46…

MALICIOUS

PDF

85.7 KB Created: 2021-09-07 20:45:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 21c3111ee935cbd53dbe970159ef0381 SHA-1: 2283105721682989bca275c9989e4d4a643e652c SHA-256: b4c9c6a724165a463336ffbdd35d8d0dfb67ae04e4e6ac262703091b53953805
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage. The presence of multiple external URIs, including those on potentially disposable hosting, suggests an attempt to distribute a secondary payload or phishing content. No scripts were extracted, but the overall structure points to a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crewmak.ru/uplcv?utm_term=litany+of+the+saints+latin+pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/d3d1fa21ead4960118fbfe48d9fd9253/8947684911.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1608401ad21527---mulikulufilij.pdf
    • https://weboonline.com/ckfinder/userfiles/files/29603422766.pdf
    • http://izumrud38.com/ckfinder/userfiles/files/40403336082.pdf
    • http://ayurvedicclinic.org/userfiles/file/37395875994.pdf
    • http://le-bouquet.be/userfiles/files/4690017857.pdf
    • http://broadviewlibrary.org/uploaded_bvlib/file/4656418709.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac0d004ece---23464929489.pdf
    • http://www.hermosabeachbungalows.com/userfiles/files/36905561342.pdf
    • http://a-aqua.fr/ressource/site-image/files/48580948372.pdf
    • http://vervesimuhub.com/userfiles/file/pomabuzitowarobelak.pdf
    • https://amrapalispot.com/userfiles/file/xosetibowegof.pdf
    • http://xz-brand.com/ckfinder/userfiles/files/64446605840.pdf
    • http://alternatifmedikal.com/img/userfiles/files/24850301293.pdf
    • https://breedlife.com/upload/files/5146725387.pdf
    • http://pizzeriagiganti.ro/imagini_ws/57397041555.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a04b4ed443c---10221520048.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16113cc2103558---zudava.pdf
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/i07un3a7ldkc1m94snvsecd31g/84653380933.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb49bfacaa5---sivedujinukose.pdf
    • https://latework.cz/soubory/70151327348.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/2umcped3l4p0l8j16hp7g2bhvu/tojidanerukivusaridafag.pdf
    • https://rocksoliddesigns.biz/userfiles/file/bodaxi.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/7cdce298db05795e0591fd7b62cbedc6/20429793603.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16107199d13b24---foderebudafod.pdf
    • https://fallsplat.se/file/wadekefor.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_off0000e7cf.bin
c944ecc5f3ae97e4d07b1335f327e92ddf46645be07b4310083087686de240b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7CF 10568 bytes
font_01_sfnt_off0000ffde.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDE 16792 bytes
font_02_sfnt_off000117f0.bin
fafddc581ad317c00bb40dd1bbb7343fb361f8d6ec992a5b41b6654666d03509
pdf-font-stream PDF embedded font (sfnt) at offset 0x117F0 18776 bytes