Malicious PDF — malware analysis report

Static analysis result for SHA-256 1335fd38cd0af19d…

MALICIOUS

PDF

81.2 KB Created: 2021-04-02 16:19:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 062eaf4a94097fe6653b1fc47e1ef144 SHA-1: c83e8774f8bfe2d6fc6c3cad1188fa805f161cdd SHA-256: 1335fd38cd0af19d11b8704effed0cad609f855419d042036d775fade41be522
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm. Several heuristics indicate this is a link farm on disposable hosting, with 30 distinct links pointing to various PDF files. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or distributing further malware. The embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://golowaki.ru/123?utm_term=php+fatal+error+class%2527+numberformatter+not+found PDF link annotation
    • https://relorurexo.weebly.com/uploads/1/3/5/3/135391300/19e636.pdfIn PDF document text
    • https://cdn.sqhk.co/rotexopapi/aGyXkfc/yellow_book_cover_creative_design.pdfIn PDF document text
    • http://luminar3-download.xyz/vimavofiwikebugafe26o9.pdfIn PDF document text
    • http://24goodstore.site/19280229149h0lvx.pdfIn PDF document text
    • http://creditscorerepair.info/parts_of_speech_quizlet_12th_gradeal8n8.pdfIn PDF document text
    • http://picsonair.com/751340433416i59y.pdfIn PDF document text
    • https://salexutoxor.weebly.com/uploads/1/3/4/7/134761189/99e9467bc82.pdfIn PDF document text
    • http://iwhite.space/20689053412pilw6.pdfIn PDF document text
    • https://bogilerilixami.weebly.com/uploads/1/3/5/3/135345361/mivixebisunat.pdfIn PDF document text
    • https://cdn.sqhk.co/dedikifefisu/aOKjdhd/allen_bradley_plc_software_rslogix-_500.pdfIn PDF document text
    • http://luxshop21.site/khloe_kardashian_agezhf0a.pdfIn PDF document text
    • http://znakomstva69.space/arcade_2002_old_games_unblockedgxdyz.pdfIn PDF document text
    • https://jibowosiz.weebly.com/uploads/1/3/4/6/134632869/3633316.pdfIn PDF document text
    • https://cdn.sqhk.co/jaxabofapuw/7TQjdhd/movie_matinees_today_near_me.pdfIn PDF document text
    • https://cdn.sqhk.co/reretukida/TYhjvo8/wujuzenomaretopiwutopaset.pdfIn PDF document text
    • http://cmb-societe.com/debonub6tn6y.pdfIn PDF document text
    • https://gozowejikagigu.weebly.com/uploads/1/3/5/3/135345496/dikesuxuxoz-donuradipop.pdfIn PDF document text
    • https://jenafowumavadas.weebly.com/uploads/1/3/1/4/131437472/jidotaluxelofan_mapovif.pdfIn PDF document text
    • http://tk-time.site/wetekibwfvv.pdfIn PDF document text
    • https://cdn.sqhk.co/zunezafi/crjjOgj/49268436455.pdfIn PDF document text
    • https://cdn.sqhk.co/lojadisexudo/jxjivha/75728398364.pdfIn PDF document text
    • https://cdn.sqhk.co/puxedimuwo/hcIeNjf/off_the_road_mod_apk_free_shopping.pdfIn PDF document text
    • http://simkosa.website/anti_theft_alarm_mod_apkdca4l.pdfIn PDF document text
    • https://wutusexiradolo.weebly.com/uploads/1/3/0/9/130969471/c37f9.pdfIn PDF document text
    • https://cdn.sqhk.co/xelalizogim/gd5jbha/warzone_season_6_release_date.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • 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_off0000e5ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BA 5572 bytes
SHA-256: 6d5563cb8a8a37135fdfe28cd2b7f71a00a525d378694cb40719b3286958d856
font_01_sfnt_off0000f882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF882 11992 bytes
SHA-256: 71f27854717b05fd1b12f3947a747f7fbdc1a11acd9a7cae5896a5c16ab82dc3
font_02_sfnt_off00012110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12110 16312 bytes
SHA-256: 975089639afea594160f6daa1ae948ffc4125994d61a9fd32dce02580f7b6b15