Malicious PDF — malware analysis report

Static analysis result for SHA-256 1369c613782175a9…

MALICIOUS

PDF

76.0 KB Created: 2021-09-18 08:20:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: de845f593ed4ec8f30467aec315caf8e SHA-1: f9d4bebffec72af1852f2e9e37f7e0b5027d8bf4 SHA-256: 1369c613782175a9852ee62d49588563245f14fb7736c9402acff1cfb8e89d8b
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. It contains numerous external URLs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and the presence of many external links point towards an attack pattern involving directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://synerhu.ru/uplcv?utm_term=81+is+prime+or+composite PDF link annotation
    • https://jajugroup.com/ckfinder/userfiles/files/vibitufifidefalumovo.pdfIn PDF document text
    • http://ch-bovi.com/upload/files/96929247216.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/51169194865.pdfIn PDF document text
    • https://ratco-hardware.com/Ups/files/95512986290.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614087098527d---tepore.pdfIn PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/33740096073.pdfIn PDF document text
    • http://www.kevimotor-rock.hu/files/files/19710197385.pdfIn PDF document text
    • http://myconnect-thailand.com/image/upload/File/gobewuru.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/2254495656.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/ximabe.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/5881378415.pdfIn PDF document text
    • http://kliknetezde.cz/admin/obrazky/file/nukapanolomapejun.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/73177034964.pdfIn PDF document text
    • http://qdjshg.com/files/file/rumawobedezexopu.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/bonazu.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/jovibufemanaxesobokud.pdfIn PDF document text
    • https://rainbowprinter.com/app/webroot/files/file/woluzavarejabejorosekasig.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/rejuwu.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210918065928.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/46301954455.pdfIn PDF document text
    • http://stefani.cz/fck/file/93607329206.pdfIn PDF document text
    • http://aeon-dev.com/uploads/files/202109151646595428.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/zevoxamewulepase.pdfIn PDF document text
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/wazijisomifese.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_off0000c3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3F7 17788 bytes
SHA-256: 55c2990b0364ff19209e22b1baabd843047d4153da3a391bca241bbf487eca79
font_01_sfnt_off0000f288.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF288 10384 bytes
SHA-256: 218f910a05409bccc3cc28a9b8a3812023f08392a50f8b9668b52cec72965e25
font_02_sfnt_off00010a1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A1B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1