Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1028bf65ff21ddc…

MALICIOUS

PDF

71.8 KB Created: 2021-06-10 15:46:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: cdc8b1d4aba3e955876d7cf8a5123bf8 SHA-1: 746b7f4c9a6bb3937cc6f701fa7bbc4026aca6dc SHA-256: c1028bf65ff21ddc8c7dd4cf81ccb6e562f656e30578d2d1d4dbfcbb46c4fcf3
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous external URLs, many of which point to disposable hosting or redirectors. The primary purpose appears to be directing users to potentially malicious content or phishing sites, rather than delivering a direct exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://druttle.ru/123?utm_term=teaching+strategies+gold+interrater+reliability+certification+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4466364/normal_5ff8f34c326b1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416790/normal_60100bc4d23f9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4528876/normal_5fe60ea608619.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409801/normal_603913b2336ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451555/normal_60450bf6130c8.pdfIn PDF document text
    • https://zizuralozirufu.weebly.com/uploads/1/3/1/4/131483034/xanefan-nuxumi-rivolegepa.pdfIn PDF document text
    • https://nubiduxabegi.weebly.com/uploads/1/3/1/8/131871606/3199938.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490929/normal_5fc71aac61f58.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366011/normal_5fec8c2ae5a27.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4470380/normal_60b3ef2423b1b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449170/normal_602c49b7bd026.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/b91081aa-710a-494e-b5f7-86e1835b76b1/how_to_connect_kyocera_printer_to_wireless_network.pdfIn PDF document text
    • http://rukutuxeriro.pbworks.com/w/file/fetch/144561168/burrito_bison_mod_apk_everything_unlocked.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d34df5c7-13f7-428a-aafa-c6ab12cd3cae/tuvekar.pdfIn PDF document text
    • http://rasovuxosew.pbworks.com/f/funonarofozepisus.pdfIn PDF document text
    • http://wuvebag.pbworks.com/f/lefepug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7fd466da-e41b-4ca3-896e-571a615857f5/how_to_connect_bose_soundlink_speaker_to_alexa.pdfIn PDF document text
    • http://suzojadek.pbworks.com/f/narutabaxelilumibebo.pdfIn PDF document text
    • http://lomexalipele.pbworks.com/w/file/fetch/144651645/2701983003.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA24 5356 bytes
SHA-256: 3cdd5d5936a1d86952add5e8e4ac13f735eab4467d980d69c28be27866540ecd
font_01_sfnt_off0000dc5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5B 10800 bytes
SHA-256: 2a39e5245a6e1b3923e8d941f5e32d646f1749744e34fcb2bd2b4e18e8cf8049
font_02_sfnt_off000100af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100AF 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c