Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a8cb9b8530b303…

MALICIOUS

PDF

81.9 KB Created: 2021-03-30 03:52:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 5f2c6433b9f6cf17381ee04dacc635c0 SHA-1: b6742dbcb7965b5a791521950ed665c039e2f8f1 SHA-256: 88a8cb9b8530b30377369d94f52a84e35ad26ae35be81bbc46a5a8fb65e273ba
124 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to known malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains references to product support (Hewlett Packard LaserJet 1100 USB cable), suggesting a lure to trick users into clicking the malicious links. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 4

  • 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 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=hewlett+packard+laserjet+1100+usb+cable In PDF document text
    • http://tekplafond.xyz/lininetizajemasw266.pdfIn PDF document text
    • http://lolkek.xyz/realspace_broadstreet_desk_assembly_instructionskqyp7.pdfIn PDF document text
    • https://cdn.sqhk.co/nexetifosam/hoxkG3n/dowajofofodibuvedifufub.pdfIn PDF document text
    • https://zuwejuropuri.weebly.com/uploads/1/3/1/6/131606208/1622662.pdfIn PDF document text
    • https://gorogonib.weebly.com/uploads/1/3/0/7/130775466/5869158.pdfIn PDF document text
    • https://pedasivu.weebly.com/uploads/1/3/5/3/135387907/7442548.pdfIn PDF document text
    • https://cdn.sqhk.co/vimewiki/iitigq5/lupagelufidazoxuwezajo.pdfIn PDF document text
    • https://cdn.sqhk.co/kidimezamos/EsgfiaI/67587943070.pdfIn PDF document text
    • http://hookup154.space/klaida_3271_meezoe51n.pdfIn PDF document text
    • http://easycreditscore.info/hebrew_greek_dictionary_free_downloaduvhmk.pdfIn PDF document text
    • https://norusukesalija.weebly.com/uploads/1/3/4/3/134356509/4891d444bbdfa.pdfIn PDF document text
    • http://moitender.org/61469271887vu4c4.pdfIn PDF document text
    • http://a1metromovers.com/toduwenugibakegedpiup.pdfIn PDF document text
    • https://cdn.sqhk.co/wafavalufa/4lhfwgh/suxipesidananaxisifil.pdfIn PDF document text
    • http://habercigo.com/7128646872176lnx.pdfIn PDF document text
    • https://sisilodoja.weebly.com/uploads/1/3/1/4/131406442/xetuvinezitul-nunuriwiniwuvud-jalutoxamerupa-favelamofevumet.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/aa0549df-c1c9-4511-9d53-6f1f6086366c/is_the_ford_crown_victoria_a_good_first_car.pdfIn PDF document text
    • http://pazizota.rf.gd/93802131395.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dff515a-6bc9-468b-85c8-680da13905a0/reservation_blues_sherman_alexie_audiobook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bccf086-ccf2-4546-81d2-959baed4d3dc/31698520732.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11935ede-d019-4321-9875-fe9fb8f0fd8e/8955844308.pdfIn PDF document text
    • http://suniwuvujibo.epizy.com/complex_numbers_part_1_worksheet.pdfIn PDF document text
    • http://figadadir.rf.gd/77454079000.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af853ff7-881c-4d23-a28e-09ecd486d2e5/19083025164.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_off0000f43d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43D 5212 bytes
SHA-256: d4af6eae99b2d337e8665bb128f1a69a338a8d4f248745653568da5ed6f90cce
font_01_sfnt_off0001061c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061C 11044 bytes
SHA-256: 44c6b9d3e96e4b061e52c831d33b775f5b39c4d89db38eddebe7ec9452b18def
font_02_sfnt_off00012bc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC9 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e