Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4a260098f662fea…

MALICIOUS

PDF

75.4 KB Created: 2021-09-09 22:04:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 56b66826b43aea2324705efc6938bbc5 SHA-1: cb31ee94365fb6256689c1df63dd3f177118274b SHA-256: d4a260098f662feacb84a0b8197c865a0f7d5042c460745db6faddc1ccb9fd28
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, many of which point to other PDF files on disposable domains, indicating a link farm or redirection strategy. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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 http://sdhmladavozice.cz/userfiles/file/99821951131.pdf In PDF document text
    • http://gtlmarinefuel.com/userfiles/file/siwodilidum.pdfIn PDF document text
    • https://rm-parketi.si/uploads/28404382096.pdfIn PDF document text
    • http://robfredo.com/userfiles/file/30375133622.pdfIn PDF document text
    • http://toyotarent.hk/FileData/ckfinder/files/20210903_C9000659130E519A.pdfIn PDF document text
    • http://saconsultancy.com/userfiles/file/nanepupodapatetuge.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/wavakodesegileraxen.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/89509233506.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16131ab26b174e---goloxufolu.pdfIn PDF document text
    • https://jackyrouxmethode.com/userfiles/file/lajurelazagevunepov.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210903_AC0B3D234E84AB15.pdfIn PDF document text
    • http://kreativitaet-stadlhofer.at/global/images/userfiles/file/76350488583.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/kovimonikak.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/kamukisedotaguf.pdfIn PDF document text
    • http://lokalizacja-gps.pl/userfiles/file/gofomizobolaridata.pdfIn PDF document text
    • http://doks-films.com/pcms/content/file/99330867836.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/58034145778.pdfIn PDF document text
    • http://mcenterdk.ru/fck_editor_files/files/26130556081.pdfIn PDF document text
    • http://s13cf5ef.alojamientovirtual.com/ropalaboralbarata.com/userfiles/file/74315446033.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/dinejuvegevanagowanadefuv.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/52236033557.pdfIn PDF document text
    • https://kawanmto.info/contents/files/piviwaladimenewedoriwu.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/f6cd7ac5d834fe9da0ec4c77554cee2c/28660969504.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=download+pokemon+ultra+sun+apkPDF 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_off0000c295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC295 17360 bytes
SHA-256: 90a2ad6c69ee4aef4d2a2a4647d5a4dab343383c6850baccc07d77d05ddf5297
font_01_sfnt_off0000ef21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF21 10740 bytes
SHA-256: fd411043b02e7058d17644e1ef1f75deb4900bbda662d195d84309d2de6c5bb1
font_02_sfnt_off000107e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1