Malicious PDF — malware analysis report

Static analysis result for SHA-256 428c9ed584fbc338…

MALICIOUS

PDF

79.2 KB Created: 2021-09-22 09:47:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ebcedd9fe846168b258513d9b3258d29 SHA-1: e6318b11e48b8fbad760fd71d4cf2ec87fcbdfde SHA-256: 428c9ed584fbc3380c50695d1f54329a3eded66917414dc08ea3841dd461e3bf
146 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 external URIs, with one heuristic specifically identifying it as a link farm on disposable hosting. While no scripts were extracted, the structure and numerous unknown URLs suggest it's designed to redirect users to potentially harmful sites, possibly for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://dveropolis.ru/upload_picture/49794103962.pdf In PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/xarejodu.pdfIn PDF document text
    • http://skpizzasubs.com/uploads/files/90822449309.pdfIn PDF document text
    • http://sparkpro.lv/content/file/4688718342.pdfIn PDF document text
    • http://tajilin.com/upload/files/82015621838.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/piwetoririrelamaru.pdfIn PDF document text
    • https://incense888.com/uploads/files/202109140755201613.pdfIn PDF document text
    • https://anukulagrotech.com/ci/userfiles/files/56478766103.pdfIn PDF document text
    • http://swaptoys.org/ckeditor/uploads/files/91551205598.pdfIn PDF document text
    • http://incomingmakedonia.com/files/files/48806230521.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/46268904062.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/guwugez.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/botuvisekawovuzojuk.pdfIn PDF document text
    • https://lawrenceyezersky.com/userfiles/file/17267450411.pdfIn PDF document text
    • http://cheniou.handysociality.com/upload/files/jorukusedanasutewexoseb.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/wapobisonesiv.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342cadb206d---tubujodojirim.pdfIn PDF document text
    • https://gilbertems.com/videos/file/welikotuwuwofu.pdfIn PDF document text
    • https://www.thaiahpa.com/flash/files/vekizo.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/70100465651.pdfIn PDF document text
    • http://forspeed.cz/ckfinder/userfiles/files/zidumato.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/gibolaloporepidobixasepur.pdfIn PDF document text
    • http://meskerjager.nl/media/files/11351843864.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/92260453213.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=how+to+stop+audio+ads+on+androidPDF 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_off0000d10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD10A 10384 bytes
SHA-256: 8b054fe07034699a5dbee1f6586c166d06580551d200956b7d77f5ebb229c152
font_01_sfnt_off0000e8a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A5 17632 bytes
SHA-256: 905d9cf67213adf3323406425ad2355e798c3fc08e257be27c6db3b0c543de21
font_02_sfnt_off000116d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1