Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1818f4c53614c91…

MALICIOUS

PDF

78.9 KB Created: 2021-09-14 12:07:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a04b3cba86f7c4fc111e9d29f176a517 SHA-1: 2e557e4e2a86f74160fc067b6ebe8d6a0877eee4 SHA-256: e1818f4c53614c913138dd42fc13ea737ee927192fbdae3d9a8dca827a4264c4
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external sites, suggesting a phishing or malware distribution scheme. The PDF structure and the presence of many links on potentially disposable domains further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://4cmedica.com/ficheiros_upload/file/94536128119.pdf In PDF document text
    • http://linza-market.ru/upload/files/kawawazetonojof.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/weduribadexipexug.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/98921621377.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/widukab.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/jitavotoworux.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/7c399fe46f30a37f4479d44ba02e2053/64183881123.pdfIn PDF document text
    • http://blankheich.de/images/uploads/file/59948306626.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/13214552245.pdfIn PDF document text
    • http://faceconnects.com/ci/userfiles/files/seripalulotivezuzevotobin.pdfIn PDF document text
    • http://macro-e.com/app/webroot/userfiles/files/64413403257.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3b7107aa5---61769452303.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/84992651524.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/18045124494.pdfIn PDF document text
    • http://stroykap.com/application/views/stroykap/userfiles/file/naxobimuvajube.pdfIn PDF document text
    • http://fgosvo.ru/files/files/woxujuduveborupes.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/39789375203.pdfIn PDF document text
    • https://wroclaw-effatha.pl/grafiki/file/30295053959.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/658682243.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/37574500077.pdfIn PDF document text
    • http://gajagotour.com/UserFiles/file/tanobesigifi.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/55210358046.pdfIn PDF document text
    • http://peak-experience-europe.com/images/blog/file/nigimufife.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/9416901227.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=android+printer+settingsPDF 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_off0000d381.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD381 10340 bytes
SHA-256: a59d5b86fc051f76d11d72a092812d486a0913a84203c8d7732e3e75b84f2558
font_01_sfnt_off0000eabf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEABF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000102d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D1 17088 bytes
SHA-256: c36d0b84d749329a14a329a58ff5ac39bb4596d39a8eb596dd688775c59cca16