Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a23910fccdd098a…

MALICIOUS

PDF

82.0 KB Created: 2021-03-10 15:08:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: c16ce8a83b0f9616f0352f574e4a0c60 SHA-1: f41f4ba5ff3392fc9e5f9ea3865f2d2d74975dce SHA-256: 0a23910fccdd098ac2382acfe81d022d797e6d9d414fe86cfd3e40f59b4aeb6e
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to host malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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://baarspo.ru/award?keyword=b+com+hons+10+year+books+pdf PDF link annotation
    • http://nakozek.mypressonline.com/anamnesis_formato.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424646/normal_6041e37273d47.pdfIn PDF document text
    • http://bejisosubonito.sportsontheweb.net/jowerefa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372682/normal_602050e3c3602.pdfIn PDF document text
    • http://gejesixave.scienceontheweb.net/stairway_to_heaven_bass_guitar_pro_tab.pdfIn PDF document text
    • http://nigoguno.scienceontheweb.net/who_is_gretel_in_the_boy_in_the_striped_pajamas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483591/normal_60397abf84925.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443574/normal_5fd63e0f8584c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402289/normal_6041d6145d1af.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388818/normal_6009471adf607.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371005/normal_5fd9918750ea5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384851/normal_601079edbdd2a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://uploads.strikinglycdn.com/files/0fcee79a-5e0d-41b4-8ccc-28246bb980b9/54136829070.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e157120-fa04-40f2-8501-e658d7f536d6/boporiguzegavib.pdfIn PDF document text
    • https://696f1bd8-06c3-47a7-a8f7-e83e17ec8d18.filesusr.com/ugd/5ad03d_79f0e9e4beee4e1ea9f6a32e8e32b6dc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/256196ac-30b0-4048-812b-ca500b4ef144/46467798583.pdfIn PDF document text
    • https://19e6fc83-c281-4d06-93fd-e8b16a02b90a.filesusr.com/ugd/ce5d00_a183677d6d7c4cfbb34fc5841c2c4b7f.pdf?index=trueIn PDF document text
    • https://44034db3-6cdd-4729-adf3-7ccd6afcf354.filesusr.com/ugd/9fe9cc_881da6314bde4bc8bfda5399561ef82b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b85c91e9-508a-48d0-905f-475389ffa2eb/how_to_use_oregon_chainsaw_sharpener_23736a.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE20 5912 bytes
SHA-256: 663ebb540e520c3f1e67a1610bc8bfcd83072f70de53229d97440f7647a679ff
font_01_sfnt_off0000f222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF222 10648 bytes
SHA-256: 69ba0cb69ed3e269503cbe0e8dbba9af198328877e21ab0e30756cdbab5a918c
font_02_sfnt_off000116c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C6 16164 bytes
SHA-256: ead7fd593d7f5feef6f283420e9b55f8fa4552f107c64b0063d474dd3355abd8
font_03_sfnt_off00012c1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1B 3696 bytes
SHA-256: 9bb21aa1b44f9bc5b781b6eabe6fb92a260aedf4bc578533986ab122167cdeb6