Malicious PDF — malware analysis report

Static analysis result for SHA-256 f59db76fd571bc6b…

MALICIOUS

PDF

80.3 KB Created: 2021-03-18 16:04:38 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 17db9935606da1aead01222ddffef835 SHA-1: 63ba762311dd07e80548400e6dc1f4f97948fa48 SHA-256: f59db76fd571bc6b3a682f4f65a2977947644de96b6c8a027e2d1ce67751c743
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was identified as malicious by ML classifiers and ClamAV, flagging it as a phishing trojan. It contains a large number of external links, characteristic of a link farm designed to redirect users to potentially malicious sites. The document body is heavily obfuscated and unreadable, providing no direct clues about its purpose beyond the presence of metadata indicating it was generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://kuzutuzo.ru/award?keyword=april+2020+current+affairs+quiz+pdf PDF link annotation
    • https://cdn.sqhk.co/visobipibe/GhjihUW/the_ordinary_serum_for_whiteheads_and_blackheads.pdfIn PDF document text
    • https://cdn.sqhk.co/muvifisi/hfAhgnQ/pelazanixowodopuzuw.pdfIn PDF document text
    • https://cdn.sqhk.co/jatizaru/hjbji1K/14936939916.pdfIn PDF document text
    • https://cdn.sqhk.co/bozutebux/dghd6gg/vefovubadezumekirafefi.pdfIn PDF document text
    • http://likododolokopaj.iblogger.org/zamalizipepafozaji.pdfIn PDF document text
    • https://cdn.sqhk.co/vekuperik/fMCiiJJ/kesoru.pdfIn PDF document text
    • http://tetupamino.mywebcommunity.org/35164554233.pdfIn PDF document text
    • https://cdn.sqhk.co/dapalufited/ggqjdiQ/bts_korean_music_festival_2014.pdfIn PDF document text
    • https://cdn.sqhk.co/fukonovum/cge8Hia/drill_master_polisher_waxer.pdfIn PDF document text
    • http://sesizuxewewax.mygamesonline.org/tp-link_tl-sg1005d_v8_5-port_gigabit.pdfIn PDF document text
    • http://ganitigusawev.mygamesonline.org/27700375667.pdfIn PDF document text
    • https://cdn.sqhk.co/lokabawopup/ha5VPif/32134157232.pdfIn PDF document text
    • https://cdn.sqhk.co/gisatajofo/higghjw/facebook_portal_alternatives_2020.pdfIn PDF document text
    • http://gamukanemafutu.mywebcommunity.org/88155194763.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wobuwikag.epizy.com/cystite_hmorragique.pdfIn PDF document text
    • http://zolibexusago.epizy.com/excel_vba_2019.pdfIn PDF document text
    • https://8d2868a3-57b7-484c-81f6-493c1c4f5daa.filesusr.com/ugd/a8ca0f_3501063f5e3d47519a16464e27d15afb.pdf?index=trueIn PDF document text
    • http://wupeguliv.epizy.com/lidolitenaxozutafot.pdfIn PDF document text
    • https://0fdd9f25-8366-4660-9463-376fd915ad39.filesusr.com/ugd/c16cf9_56f1b0b51ea6432d99581330004a5093.pdf?index=trueIn PDF document text
    • http://woxedizoxe.rf.gd/vacation_2015_parents_guide.pdfIn PDF document text
    • https://51bf459c-6b46-41b0-863f-532cf8a77e0d.filesusr.com/ugd/2eedf1_267cb7b4c8654dccbf0caa8e1673c7ab.pdf?index=trueIn PDF document text
    • http://dudulexo.epizy.com/21802135589.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F2 5588 bytes
SHA-256: b71a1966b792bcfc04d00da77d1dda0fd713875b4c8396dc5020aa9f3554b9ac
font_01_sfnt_off00010c07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C07 11384 bytes
SHA-256: 69ada1e3d07daf2efaced8bd174040bde6debdc27083c4cc0db3a5097fc255c3