Malicious PDF — malware analysis report

Static analysis result for SHA-256 16123c3dc1c149e2…

MALICIOUS

PDF

76.3 KB Created: 2021-09-19 01:51:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4333983f27e1a60b96b8192d324a214a SHA-1: 218fa78a34a76a946abf91839f13d0c4f8bf8f90 SHA-256: 16123c3dc1c149e2554e1dc2bb04aa01caff25eb17ce9a35d81c596ca92846be
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. Heuristics identified it as a link farm with numerous external URIs pointing to disposable hosting, suggesting an attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded links strongly suggest an intent to exploit users through deceptive 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 http://doks-films.com/pcms/content/file/94699460495.pdf In PDF document text
    • http://aybar-gallery.com/userfiles/files/59368232542.pdfIn PDF document text
    • https://fpcofmacon.com/nbloom/fckuploads/file/53609785868.pdfIn PDF document text
    • https://easy2ticket.com/upload/files/zoxabor.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/697689244.pdfIn PDF document text
    • http://myshiou.com/uploads/files/202109160224584862.pdfIn PDF document text
    • http://hoilhpnqbthanh.com/upload/file/5739669323.pdfIn PDF document text
    • http://hajnysport.cz/FCK_userfiles/file/96161021570.pdfIn PDF document text
    • http://papienbanana.com/user_file/file/larerokam.pdfIn PDF document text
    • https://serka.com/serka/upload/files/dimilisedozonov.pdfIn PDF document text
    • http://mindennapi.hu/upload/file/87119032434.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/7745ecba5a12b8c95b7a6642860ce083/jojoma.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a072335354---28610893325.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/totupasavusa.pdfIn PDF document text
    • http://ustunongel.com/image/files/18704209008.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/nupeluvegelavav.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/60839554033.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/sujamufarulijegulikekazag.pdfIn PDF document text
    • http://csc-020.com/userfiles/file/20210913171635_cgatyi.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/28538517142.pdfIn PDF document text
    • https://bimetoor.com/basefile/bimetoorir/files/gexaf.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/42801909061.pdfIn PDF document text
    • http://dallapietamarchisio.it/userfiles/files/dozonevorugux.pdfIn PDF document text
    • http://studioghittigargnano.com/userfiles/files/finuxujudokawesigaxujod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=mad+skills+2+mod+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_off0000c7b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7B5 10324 bytes
SHA-256: 8b1523be3f09e253897e74fa7df68e7992626eeb087c27ab8bb134f6382bece2
font_01_sfnt_off0000def6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF6 17060 bytes
SHA-256: ae04c358f25bf22a4d57bf395eb97d3d101b73555872d9f0ed4cf76eb56d17cc
font_02_sfnt_off00010b90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1