Malicious PDF — malware analysis report

Static analysis result for SHA-256 26eab6d43211ff0d…

MALICIOUS

PDF

79.8 KB Created: 2021-09-10 10:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 6f33ed9bf057adbda931fc6f2152ad2a SHA-1: dffb05634eb1998859d2d6eb3f7afcaf7bdbf6e5 SHA-256: 26eab6d43211ff0dec93003b37107ee685c823b1a25b2428ad3e2eda86ffd5dc
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple links to external PDFs hosted on potentially disposable domains, indicating a phishing or malware distribution attempt. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest malicious intent, likely to redirect users to a malicious payload. The ML classifier and ClamAV detection further corroborate the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://twsl.mingann.info/upload/ckfinder_temp/files/20210907165451.pdf In PDF document text
    • https://xn--nmqu14inmf.com/upload/files/42830456028.pdfIn PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/vorubikatuk.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/92360815533.pdfIn PDF document text
    • http://peak-experience-europe.com/images/blog/file/xuxelunen.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/wulujidabarejimamato.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090112211173499.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/30296861683.pdfIn PDF document text
    • https://linlinline.biz/js/ckfinder/userfiles/files/varevefezimu.pdfIn PDF document text
    • https://reparation-mobile.net/userfiles/file/baderakilowivabuv.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/62051134390.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/bekeruxajej.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210907_B111DE73273A3C12.pdfIn PDF document text
    • http://rococosofa.com/files/files/forarebeje.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/kizepi.pdfIn PDF document text
    • https://teamcode.net/upload/files/99347508902.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/vivigerasemuxamipulavu.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/gikiwefotejujeranawa.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/80192062001.pdfIn PDF document text
    • http://phukiendoxe.com/media/ftp/file/29676897480.pdfIn PDF document text
    • https://uslugiinzynierskie.com/eurostyl/photos/file/52099661075.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/47542422549.pdfIn PDF document text
    • https://dallaslandscapedesign.com/media/files/84197319119.pdfIn PDF document text
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/8336870290.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=android+install+wifi+certificatePDF 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_off0000d2f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB04 17904 bytes
SHA-256: 65a34b0688342a9295246156bb82b2b175a43c5e95e553c613952906cae83ccb
font_02_sfnt_off00011952.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11952 10536 bytes
SHA-256: df6cf082aab16f7f8b0b9b45852cd3c29bcbf146bfd2927e448a7d5e7e7ad8bc