Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c08092b1a6247b4…

MALICIOUS

PDF

74.7 KB Created: 2021-10-23 03:15:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: a5fa8e0e49d52188eadce893ad519984 SHA-1: b9f57e18d5fdbc30b89cf25ffdf7be7bca7cacd1 SHA-256: 4c08092b1a6247b4fb9b6e584b3ba16d52c59c4570f8fa465605fc00656a071d
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm hosted on multiple compromised websites, directing users to download further PDF files. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates that the document likely instructs the user to open a password-protected archive, a common tactic to bypass gateway security. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/5c5c4603633434869597ecab072a20c9/29573426882.pdf In PDF document text
    • http://www.asap-recruitment.net/upload/file/tisebarininusetu.pdfIn PDF document text
    • http://fk-fudosan.1nino3.com/app/webroot/img/userfiles/files/2800171674.pdfIn PDF document text
    • http://esistore.de/userfiles/file/rafimexugaja.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/639da77e82bae3aad81a2d23804cbdc4/wupogasufe.pdfIn PDF document text
    • http://virtualcharityevents.com/vce_cake/files/files/pixawaxofukotasowofen.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/xuxugetadivowemivupupo.pdfIn PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/kidogurato.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/dowofotusufitijetukesot.pdfIn PDF document text
    • http://planet-pvc.com/upload/files/78711639570.pdfIn PDF document text
    • http://hzaidele.com/images/upload/File/383959056.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/45682787529.pdfIn PDF document text
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/37745291071.pdfIn PDF document text
    • https://i-try.tw/upfile/files/2021/09/24/70067992224.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/45266912931.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/72e3ec5c27baa959831f4b6d9815bd8f/30128087679.pdfIn PDF document text
    • http://labemweller.medianet-shop.de/userfiles/editor_files/file/gazoburor.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/lakapurewaxibaxowalevi.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/1c1a12527067f44b950755a2760caee2/10165771530.pdfIn PDF document text
    • https://pepsima.biz/files/file/54563164674.pdfIn PDF document text
    • http://annabarons.com/files/files/nafofofejapa.pdfIn PDF document text
    • http://studioguidobarbieri.it/userfiles/files/xamok.pdfIn PDF document text
    • http://nissanotogovap.com/uploads/images/files/39268137354.pdfIn PDF document text
    • https://mancomunidadvaldizarbe.com/userfiles/files/77519316357.pdfIn PDF document text
    • http://cabini.it/userfiles/files/torifijemoxofi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/TxADE9PCSUw/uplcv?utm_term=intramembranous+ossification+bonesPDF link annotation
    • 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_off0000bdc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5D6 18416 bytes
SHA-256: c5038755a222025faade02826d2fabbeed1efc1ef7ba20d8f9ddcf6c52184777
font_02_sfnt_off0001042e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1042E 10644 bytes
SHA-256: 121ade559c7b234b6d79847da0457de97896220fb3266a6baa6d7a2e7583d57e