Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fa348dfde2d22df…

MALICIOUS

PDF

92.9 KB Created: 2021-04-07 05:51:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 5ff06427608bb4cca1d985cf8ed4d702 SHA-1: dc773b7ec78acc986e1c6d9508eb5f0a9e56fe38 SHA-256: 8fa348dfde2d22df34eee3688e7aa309456742ebb4a89fabd9629c2c6efd85f8
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to disposable hosting and are likely part of a link farm designed to direct users to malicious websites. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' specifically identifies a link to 'yafferge.ru' as a known malicious redirector. The ML classifier and ClamAV also strongly indicate maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • 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.
  • 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.
  • 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://yafferge.ru/strik?utm_term=onkyo+tx-sr608+fernbedienung+problem In PDF document text
    • https://baseparefawufif.weebly.com/uploads/1/3/1/4/131453046/lasizofoworilutez.pdfIn PDF document text
    • https://rajexomogalifi.weebly.com/uploads/1/3/4/8/134891851/kowamukeki.pdfIn PDF document text
    • https://baxemazone.weebly.com/uploads/1/3/0/7/130739829/2213096.pdfIn PDF document text
    • https://cdn.sqhk.co/fexivijemozu/IhjcBgg/keynote_templates_envato.pdfIn PDF document text
    • https://cdn.sqhk.co/parikozug/bhhZahi/betavesafinosav.pdfIn PDF document text
    • https://cdn.sqhk.co/satukevaguka/iVdL1ig/personal_swot_analysis_examples_of_threats.pdfIn PDF document text
    • https://cdn.sqhk.co/xudapurofoz/xyjgge4/roman_adventures_britons_season_1_caches_6-_10.pdfIn PDF document text
    • https://cdn.sqhk.co/guregame/Glclidv/2_player_murder_mystery_game_ps4.pdfIn PDF document text
    • https://cdn.sqhk.co/gilubibawi/jghiG0R/jubakexobarix.pdfIn PDF document text
    • https://vugovarekuluf.weebly.com/uploads/1/3/1/6/131607096/4807252.pdfIn PDF document text
    • https://gojesewemuvi.weebly.com/uploads/1/3/2/6/132681304/sikakemavuw.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/5fbb427a-dcfb-48aa-9032-0f90c1db7b44/how_to_turn_on_onn_walkie_talkie.pdfIn PDF document text
    • https://s3.amazonaws.com/vuxalirudidel/how_to_heal_chilblains.pdfIn PDF document text
    • https://s3.amazonaws.com/xovekolamoxe/duzigekekuboloset.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a1318fa-5d26-47e8-8cbc-8914b82b8ab1/40403110825.pdfIn PDF document text
    • https://s3.amazonaws.com/varoximu/programming_for_beginners_python.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1608d97b-c9bd-4fc1-8639-626828bdb8c8/20552259898.pdfIn PDF document text
    • https://s3.amazonaws.com/fizufapu/rujomumesatofaputa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92a74f99-7414-46c4-a6b9-3c90d4bec16c/whiskey_words_and_a_shovel_book_set.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7fa66e7f-8d68-4666-af6c-38d12a89d117/technivorm_moccamaster_79212_kbts_coffee_brewer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9c2540b-66da-4f1a-b807-2b1bfcb8ca0b/xakefutopugijamasafaw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e5768888-8d57-40b3-957a-5eee94eeaa70/never_eat_alone_expanded_and_updated.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_off00011ac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AC5 5956 bytes
SHA-256: 2a4109e1537bd2f4f628d207624bc58693950f3a091f0a1d5527b94390a06b34
font_01_sfnt_off00012eff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EFF 11868 bytes
SHA-256: 3014a8f90550297010504d523257e20895a95c0594ebcdfb4ac3d66d67830381
font_02_sfnt_off00015687.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15687 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e