Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8aec3b5aab531c0…

MALICIOUS

PDF

75.8 KB Created: 2021-09-27 15:12:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ec37915e3a4a6e9d7bbf06baa658a80e SHA-1: 072f15f07073bf6cab463266b0f280ff1604d2d7 SHA-256: d8aec3b5aab531c006cd90d9cf45d5c78a653608486b3cfcb20e3e3bd4e9c085
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to disposable hosting, characteristic of a link farm designed to redirect users to potentially harmful sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, suggesting the document's primary purpose is to act as a lure for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=condividere+schermo+android+su+smart+tv PDF link annotation
    • https://meritumptt.pl/dokumenty/file/82772989399.pdfIn PDF document text
    • http://etalentlink.com/uploadfile/file///2021092312272059.pdfIn PDF document text
    • https://clicksnepal.grnca.org/img/files/files/vometijoguninud.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/babiwiw.pdfIn PDF document text
    • https://tsafar.ir/basefile/tsafarir/files/winej.pdfIn PDF document text
    • http://studioassociatoemc.com/userfiles/files/nonugepakefumiguwusejorep.pdfIn PDF document text
    • http://navigator-nsk.ru/userfiles/file/kunazej.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/diwomigewakenine.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/59483681134.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/fupirugopafizejotud.pdfIn PDF document text
    • https://gifarlcm.com/upfiles/editor/files/77534798349.pdfIn PDF document text
    • https://rireenfrance.com/images/upload/files/suxonap.pdfIn PDF document text
    • https://graveyards-fuj.ae/userfiles/files/30062719038.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/46253278076.pdfIn PDF document text
    • http://retroldn.com/userfiles/file/42809074267.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/93441493227.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/109838960.pdfIn PDF document text
    • http://tmacfashion.com/ckfinder/userfiles/files/fedevojavebewofexul.pdfIn PDF document text
    • http://makrostal.pl/user_images/file/81961545322.pdfIn PDF document text
    • https://tedesco.pl/userfiles/file/58221771174.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/6609001117.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/5349891423.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/77438372528.pdfIn PDF document text
    • http://ciskmv.com/css/file/moledegegimukekom.pdfIn PDF document text
    • http://e-sportis.com/images/upload/34426244454.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_off0000bdb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB4 19456 bytes
SHA-256: 849eea26b1f1390668480329514486a090fe0d1c1ac9ef3eed1f267c8951980b
font_01_sfnt_off0000f0f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F2 10784 bytes
SHA-256: 1535bf4d1fa8c68fc0688ed04f0cbe656370665600106eab78ad087f04be22b0
font_02_sfnt_off000109ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1