Malicious PDF — malware analysis report

Static analysis result for SHA-256 03d83d3195e1f799…

MALICIOUS

PDF

75.7 KB Created: 2021-09-14 04:29:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4b6e4f1fbc84ec54c1f2abf8fe73938a SHA-1: 3c9cdfec2e4b29df9a10f6c84780285914b4ecfd SHA-256: 03d83d3195e1f799b65c8f85d57edcb36f625ec550a16272f3b844a15b42265e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high-confidence heuristic flagging it as a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the structure suggests the PDF is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://laborke.ru/uplcv?utm_term=killer+instinct+gold+apk PDF link annotation
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/29425272740.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/febewewatikuxexanafavele.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/ziseginajivuzoj.pdfIn PDF document text
    • http://traslochimontalto.it/userfiles/files/21220083555.pdfIn PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/44625450831.pdfIn PDF document text
    • http://emannsltd.com/userfiles/19030258330.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/mujibeja.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/rigukisuj.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613718769f559---69851144235.pdfIn PDF document text
    • http://hfengly.dk/skoleportalen/userfiles/file/wibamipufejawoni.pdfIn PDF document text
    • http://pierrevillers.fr/mairie_files/file/tufamigopurerazovezutorof.pdfIn PDF document text
    • http://smartwealthhk.com/userfiles/95692713594.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/35624236244.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/kodanilizapusepitife.pdfIn PDF document text
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kijarodo.pdfIn PDF document text
    • https://dansobentre.net/uploads/file/594513745.pdfIn PDF document text
    • http://ke-sen.com/userfiles/file/1630623819.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/73199827327.pdfIn PDF document text
    • http://apartmany.cucoriedka.sk/data/files/moruwilalopov.pdfIn PDF document text
    • http://votejoedestefano.com/editorData/file/80679515436.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/gezix.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/niroginalilotuvivaxuxivel.pdfIn PDF document text
    • https://basisnomor.com/contents/files/31214974308.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210901163109.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/vonenozuzapenefuba.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_off0000c112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC112 18312 bytes
SHA-256: fae179afafa5433d4f82e24b0b816e693da29f43f80d0a872cb991397a7bb2b8
font_01_sfnt_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A1 10772 bytes
SHA-256: 75f1b2a861652a79a54236c4934855ade3829cefa5421a09dbfa439df9397168