Malicious PDF — malware analysis report

Static analysis result for SHA-256 82c37c5baf80daf9…

MALICIOUS

PDF

88.2 KB Created: 2021-04-04 21:42:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 68a48a2a1fc335f8798e1838df169471 SHA-1: 22cdd9c2628859896f5a62c2ef60e4d8ab3c444d SHA-256: 82c37c5baf80daf9900246445ec2eddb1f431ff03ffd01a0715cadecfaaf719f
126 Risk Score

Malware Insights

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

The PDF contains numerous external URIs, with a primary focus on a link farm hosted on disposable domains, suggesting a phishing or scam attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing. The document body, though heavily obfuscated, contains references to educational topics, likely as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://kuzutuzo.ru/award?keyword=acids+bases+and+salts+class+10+ncert+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4368955/normal_60335a126eca9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406464/normal_5fd7957ae0e4e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417129/normal_5feba23d80be8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368219/normal_60358b397c758.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482863/normal_5ff7afeb37760.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471464/normal_60559cfbd1407.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496815/normal_6031fc85d92e5.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://7fe1f042-206b-4735-a408-f56337efeeb4.filesusr.com/ugd/d34b51_7feb7fffdaf9406e9b1b0cdfe5802676.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/320f2e99-efde-44df-b8e0-65cb08b6353b/directv_genie_remote_ir_or_rf.pdfIn PDF document text
    • https://s3.amazonaws.com/fakuguvil/how_to_mix_ppg_paint.pdfIn PDF document text
    • https://s3.amazonaws.com/jojitagifuva/ralirotevakan.pdfIn PDF document text
    • https://b0b89e74-75d6-43b0-bb8f-fa2cd9bd5f5b.filesusr.com/ugd/b5ae3e_cd931a084f174aaeb81ee16e120efae2.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c24ffa8-d425-4ec0-857f-4a496344692d/wijakuxepimalobibab.pdfIn PDF document text
    • https://a1f0096d-76f5-425c-b826-5ccbd312c1bc.filesusr.com/ugd/8f8c07_9b3cc337dfca42ac87d0a8ef66cc00a6.pdf?index=trueIn PDF document text
    • https://3175e58c-9db9-4d87-bcb9-15e03531d93d.filesusr.com/ugd/c93210_478aefb620304554acf825681624dd0b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/eff2a5e2-a78b-483b-9420-84769fdec679/marlin_30-30_tactical_forend.pdfIn PDF document text
    • https://s3.amazonaws.com/xeruxaxer/but_not_for_me_piano_sheet_music.pdfIn PDF document text
    • https://77a80da1-97a3-4b40-ba11-54c6d232eb66.filesusr.com/ugd/39a0fd_707d893ca80b43968fd798e3d68ce512.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f44c3a5-e4be-4ae1-a2cb-a562c8cd1128/red_dead_online_beginners_tips.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16793843-eee4-4bb2-85c2-96ee0f62df04/3007454754.pdfIn PDF document text
    • https://s3.amazonaws.com/ditiruz/perotegef.pdfIn PDF document text
    • https://s3.amazonaws.com/vizegemawokaxe/35852847728.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_off00010edc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EDC 5152 bytes
SHA-256: 5a1520cda2c7ad73ea43dba67939e8461eb3fd19b26ed166c731386a43dbe1be
font_01_sfnt_off00012058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12058 10872 bytes
SHA-256: d617db30d72e9b3f5b75a628d9a7b343a127a6fbaa3e337d8d2110ce7f6348b9
font_02_sfnt_off0001454f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1454F 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f