Malicious PDF — malware analysis report

Static analysis result for SHA-256 21b0abbfd8e23b47…

MALICIOUS

PDF

88.6 KB Created: 2021-09-19 03:09:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 85aeec6de22f34b5892d4a98d5fb1f22 SHA-1: 4bb63127d662cac8e005c9249a1d1017d9254786 SHA-256: 21b0abbfd8e23b47b762d1717eb34c73232f38e631affef842478bfa0ec45b21
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm or phishing lure. The file's structure and embedded content indicate it is designed to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://catamma.ru/uplcv?utm_term=gta+sa+flash+mod+android PDF link annotation
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/20875333535.pdfIn PDF document text
    • http://cloudinfo01.smartevolve.com/images/ckeditor/files/28396579297.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/raloxizivududabovalez.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/gukosoridu.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161465e96532e7---fuxavafuvul.pdfIn PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210914_104748.pdfIn PDF document text
    • http://collectifff.be/imgdb/accueil/files/nevodemoda.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/61a82f56eeda8f7bff3ab9b9029776fb/41707873096.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/84434833083.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/49946851193.pdfIn PDF document text
    • https://greenways.at/userfiles/file/podaxuxofivaxiwedunobedal.pdfIn PDF document text
    • http://zhymwz.com/upfile/file/76925876348.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/89956121364.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/zajugazibugetena.pdfIn PDF document text
    • https://aqua2go.pl/galeria/file/22332896734.pdfIn PDF document text
    • http://kolbiko.com/images/uploads/file/nufon.pdfIn PDF document text
    • https://watosaphotography.com/app/webroot/userfiles/files/20210908_214419.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613949839227f---39915317686.pdfIn PDF document text
    • http://itexpertdog.nwoasis.com/upload/files/23495201350.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/2823629957.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/70064439013.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D3 18444 bytes
SHA-256: 16f6a941447ca4f2a60bbbaede3cc3af78b0af685e3493c42b162b7197bc35b3
font_01_sfnt_off0001252f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1252F 10524 bytes
SHA-256: caa37093904563015d3498cefe9344afd88e566c8261b5e3989c28fb415eb935
font_02_sfnt_off00013ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1