Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4b3ae4aa32ad156…

MALICIOUS

PDF

74.8 KB Created: 2021-03-11 05:11:38 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: cdbe7fc0924d2564730489f77a62c08c SHA-1: da2b9561fdfb792b27aa734e0d420fd1abe20d39 SHA-256: b4b3ae4aa32ad15619df3ad504ed1d1926c9916d4ad6e09476a3e2865e997d63
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://baarspo.ru/123?utm_term=endless+alleluia+piano+sheet+music+pdf PDF link annotation
    • https://bopelesi.weebly.com/uploads/1/3/0/8/130874615/ab6dc44a7e87ec5.pdfIn PDF document text
    • https://mobefoba.weebly.com/uploads/1/3/0/7/130776725/mepofodazak-jikijivuzew-tesupixanesisu.pdfIn PDF document text
    • https://cdn.sqhk.co/tewokozogop/hhhficP/classroom_management_styles.pdfIn PDF document text
    • https://begosibaluta.weebly.com/uploads/1/3/0/7/130775163/xebarut-zojejoponiwiwet.pdfIn PDF document text
    • https://cdn.sqhk.co/zonelatu/wchKMif/kilijejun.pdfIn PDF document text
    • https://cdn.sqhk.co/letaziseb/PgiNPje/mx_player_apk_new_version.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448100/normal_5fdb9439d0725.pdfIn PDF document text
    • https://mabalajobiken.weebly.com/uploads/1/3/4/0/134016714/5322277.pdfIn PDF document text
    • https://cdn.sqhk.co/rojotuwo/8Xk5eij/glory_to_hong_kong_piano_sheet_music.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383805/normal_5fefc31538ca0.pdfIn PDF document text
    • https://meluwirukumipi.weebly.com/uploads/1/3/1/4/131483006/9d2323c9.pdfIn PDF document text
    • https://dotawipe.weebly.com/uploads/1/3/5/3/135323210/9e85e728267a518.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447251/normal_5fc8ac663d3e7.pdfIn PDF document text
    • https://pesadoxemanuz.weebly.com/uploads/1/3/4/8/134852899/2673727.pdfIn PDF document text
    • https://befukifesili.weebly.com/uploads/1/3/1/4/131453358/ladame-xegisupigudesim-bodojebivafoluj-kaboluna.pdfIn PDF document text
    • https://tidosivapozagul.weebly.com/uploads/1/3/4/3/134390518/kumup.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8c1dc56a-a131-4b43-acff-3635b9115217.filesusr.com/ugd/90423f_349a41abee9c44b2b094346015a3fd29.pdf?index=trueIn PDF document text
    • https://e942959e-95af-4115-ab05-a6e38533eaad.filesusr.com/ugd/66f7a0_37f3afee863b42f79ff62b9fad86e7b9.pdf?index=trueIn PDF document text
    • https://80820154-e864-4b0c-832b-212b24169927.filesusr.com/ugd/c12414_5197e48d29a64d26b409894664e8c712.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e824.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE824 5256 bytes
SHA-256: 371c6616cb33da493cc132ff45231041c9fd4ec5ef65566194dce3ec1a510bda
font_01_sfnt_off0000f9e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E9 10460 bytes
SHA-256: 18037c9aab09a760ea48ddb75e2dc824fefa4d70a67f5b847dfb7d1640795161