Malicious PDF — malware analysis report

Static analysis result for SHA-256 b678be2371d7aba9…

MALICIOUS

PDF

74.8 KB Created: 2021-10-04 11:32:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: bdb800f51c3b9d6b73e05d7b3aa741d2 SHA-1: 94b1fe2e81471e522b083cdbcbe01107167c4f5e SHA-256: b678be2371d7aba9fc9d7ad7cc57713fc6fd29bf2b0dae3a066e207a30456f5c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, containing numerous URLs pointing to external sites, many of which are hosted on potentially disposable domains. While no scripts were explicitly extracted, the PDF structure and the presence of many external links suggest it is designed to lure users to malicious content or downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://haidangpc.com/contents/files/muterowibejidi.pdf In PDF document text
    • https://sibois.eu/userfiles/file/malojun.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210916_032607.pdfIn PDF document text
    • https://ikansambel.com/contents/files/22673153817.pdfIn PDF document text
    • https://peterdegendt.be/file/61627142303.pdfIn PDF document text
    • http://siamsankyo.com/Uploads/file/80237500039.pdfIn PDF document text
    • http://vhktn.at/images/content/files/5341439336.pdfIn PDF document text
    • http://khachsansapa.vn/webroot/img/files/tuxuvofuwigorerix.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/gizule.pdfIn PDF document text
    • https://duocvinhkim.com/userfiles/file/52893189418.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/xinonupetaxujuligakajafu.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/33043242245.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/fesisabubenitopozevoro.pdfIn PDF document text
    • http://www.wcd.com.tw/ezadmin/ckfinder/userfiles/files/25594592054.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/cc599529a1fef5845e4a293143271d76/18783750915.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/37972307327.pdfIn PDF document text
    • http://www.dkmodels.net/ckfinder/userfiles/files/sivazevenamuxijikog.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/93537796922.pdfIn PDF document text
    • http://foxgraphics.paulsfashion.in/files/86602878862.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/90364938374.pdfIn PDF document text
    • http://www.leasebridge.com/CKUPimg/files/kovukubuwulobadejepe.pdfIn PDF document text
    • https://zahidnawaz.com/UploadedImages/image/77258493743.pdfIn PDF document text
    • http://ozanetiket.com/TasarimAcarnet/serhali/upload/files/robisinuvasotovajavowetag.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/papawebiwijatowijevale.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/tasirirowakidofobud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=pokemon+mystery+dungeon+explorers+of+time+cheat+codesPDF 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_off0000b40d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB40D 19816 bytes
SHA-256: c87e3adca2e57edd1e99908b2df52af8007768a8f7c27fb1798cee4e3337d710
font_01_sfnt_off0000e864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE864 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001007b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007B 11476 bytes
SHA-256: 773fc90dfa77c79a0dbec5a92f6b7dc2a4fceeab41045e98c4933f89f788f71a