Malicious PDF — malware analysis report

Static analysis result for SHA-256 71813314eeae353c…

MALICIOUS

PDF

81.1 KB Created: 2021-03-30 14:44:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ea9900e1d8e71252a251b0e4d130aae6 SHA-1: 765ef9deac6f273d722c5ebf7f74409d32045d2c SHA-256: 71813314eeae353c7a48395fb10ba38c042ccfd6b8dc5d5f69ec8e0a24c00142
196 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to other PDFs, which is indicative of a link farm or SEO manipulation tactic. The presence of a password-protected archive lure suggests an attempt to bypass security scanning by encrypting the actual payload. ClamAV and ML classifiers also flagged this file as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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/strik?utm_term=eos+rebel+xs+1000d+price
    • http://tegotapiw.scienceontheweb.net/mebesowomanizo.pdf
    • http://kamikofonem.mygamesonline.org/easy_guitar_songs_tabs.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/58c1bfa0-2ab0-4d18-aa3b-f5784297db38/vaxoxotiminedimol.pdf
    • https://s3.amazonaws.com/tesodagiwor/pegigipu.pdf
    • https://uploads.strikinglycdn.com/files/422fd73d-787e-4a1f-a9b4-0c08f7f76acb/varejuxisogiwasawevudagel.pdf
    • https://uploads.strikinglycdn.com/files/ff7bbf89-4b84-4f4a-b85a-bc8f9f36832d/why_does_my_usb_keyboard_stop_working.pdf
    • https://s3.amazonaws.com/dudujopixejikug/81740354527.pdf
    • https://s3.amazonaws.com/putelekireza/63907823593.pdf
    • https://s3.amazonaws.com/lerezazo/7548803829.pdf
    • https://uploads.strikinglycdn.com/files/2c540b0f-d434-48ce-af41-83d0cb53a8a0/it_essentials_ite_v6.0__v7.0_chapter_8_exam_answers_100.pdf
    • https://s3.amazonaws.com/minabiwa/colours_bangla_tv_apps.pdf
    • https://uploads.strikinglycdn.com/files/be260c8d-8394-40c7-8569-299f1d48857a/28807734562.pdf
    • https://uploads.strikinglycdn.com/files/53c9a981-243e-4051-949a-73b03fe906cc/netgear_wireless-n_150_router_wnr1000v2_firmware.pdf
    • https://67d298e0-85f4-4ad4-bf36-e1ac857e42fc.filesusr.com/ugd/b6bf5b_bf96dadb0a8b45909b0f1aec4f798251.pdf?index=true
    • https://f6ce3cfb-f922-470c-9e0e-eaf724001b0e.filesusr.com/ugd/defcb2_55256f7b760e49ab8438a2d4d989e792.pdf?index=true
    • https://s3.amazonaws.com/jinabom/4258700476.pdf
    • https://s3.amazonaws.com/sebunuzu/14695841842.pdf
    • https://s3.amazonaws.com/juzowilipi/27827191517.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec11.bin
18b49b3fc69881cbafe63bb8ace801b025dfae77d65e5702a0e78b58ea12d7e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC11 4572 bytes
font_01_sfnt_off0000fc21.bin
dd53944fdb0c2b1623249172f7102196cee75f64ccb46274f9a1ff75b0a2d68e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC21 5216 bytes
font_02_sfnt_off00010df3.bin
899254641f12206dbfd2ea0216ef7d18ce0b5c1dbadc41fa4706be06d653d944
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF3 11692 bytes