Malicious PDF — malware analysis report

Static analysis result for SHA-256 812b73f624f66096…

MALICIOUS

PDF

77.2 KB Created: 2020-12-23 12:42:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8b8cbf43fef9ed47af8b5160fe8baadd SHA-1: 1c70e5360497392b60c52b7b34daa4d1513da821 SHA-256: 812b73f624f660967ca6d3f669ab7ccf46917ef6190d2617815b6b8919b77bf1
214 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, with at least one pointing to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cctraff.ru/strik?utm_term=to+do+list+recurring+tasks
    • https://lukejofavum.weebly.com/uploads/1/3/4/4/134455809/6598388.pdf
    • https://static.s123-cdn-static.com/uploads/4386613/normal_5fcc08e74c10c.pdf
    • https://static.s123-cdn-static.com/uploads/4454819/normal_5fe09cb163e34.pdf
    • https://cdn-cms.f-static.net/uploads/4462038/normal_5fa4ecc0012db.pdf
    • https://kuvenamowafave.weebly.com/uploads/1/3/1/3/131379608/fobidewurawupifol.pdf
    • https://static.s123-cdn-static.com/uploads/4417122/normal_5fcf6758df4a6.pdf
    • https://cdn-cms.f-static.net/uploads/4426960/normal_5f9ba5986b9f7.pdf
    • https://bemogipe.weebly.com/uploads/1/3/4/3/134379528/xewolikemigi.pdf
    • https://rugalasaludazi.weebly.com/uploads/1/3/4/6/134683923/kirujujaribesunugexe.pdf
    • https://cdn-cms.f-static.net/uploads/4374519/normal_5fdb085d0a256.pdf
    • https://telanadiv.weebly.com/uploads/1/3/4/4/134495792/6980129.pdf
    • https://cdn-cms.f-static.net/uploads/4378170/normal_5f91283f85edb.pdf
    • https://tokitowopune.weebly.com/uploads/1/3/4/4/134498993/natut.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/ae27ba5a-6e8b-455b-a9f4-bcbe168e00ee/8982193979.pdf
    • https://uploads.strikinglycdn.com/files/303d0606-c2c1-410b-8b56-8343a43ce4ce/pupufatuwaxi.pdf
    • https://uploads.strikinglycdn.com/files/bb357c62-16e1-4289-b38e-26cb343eff8f/larusopiviganisabupibaxi.pdf
    • https://uploads.strikinglycdn.com/files/69f2b354-026f-47b6-b5d0-f2e0342fd5b1/72615529926.pdf
    • https://uploads.strikinglycdn.com/files/6eea14b1-cf75-4723-9ed2-aa7349ca300a/bapexololujavitem.pdf
    • https://uploads.strikinglycdn.com/files/e1f0c068-3878-4a15-a16a-6cab9d0d6865/ludexupubapuludo.pdf
    • https://uploads.strikinglycdn.com/files/914565c1-bf7f-4f0f-9d6a-ea61632ccb65/84303005387.pdf
    • https://uploads.strikinglycdn.com/files/38b0b068-b3b8-4df5-8be8-cc3d4b8d5699/4928724049.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2a2.bin
66ff2df6937c6ce09f2903303b873df53d09c7909d78b58e98ec7027badb04d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A2 5120 bytes
font_01_sfnt_off0001041e.bin
48d64900907268855c61a346f6ef6a7b00e368fe525ddb46c7b15cf84f4a0c85
pdf-font-stream PDF embedded font (sfnt) at offset 0x1041E 10352 bytes