Malicious PDF — malware analysis report

Static analysis result for SHA-256 e55f3d978eb7fdf0…

MALICIOUS

PDF

80.2 KB Created: 2021-09-21 07:53:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9b3a753cdf9bd3a544bfa7d3a6186e09 SHA-1: a1a89801f56a7617cec54ba49795a3767a92938f SHA-256: e55f3d978eb7fdf014ee62023c5e4e9e4897d81c1a473024edd1021908292bd4
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it contains numerous links to external websites, many hosted on disposable domains, suggesting a phishing or malware distribution attempt. The ML classifier also strongly indicated maliciousness. While no scripts were extracted, the presence of multiple suspicious URLs points towards an attack pattern involving luring users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not 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.
  • 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 http://dges.in/userfiles/file/subojufuvo.pdf In PDF document text
    • http://goldendoodlesofthesierranevadas.com/userfiles/file/vekutazepu.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/pavije.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/161488d15b7983---51467063457.pdfIn PDF document text
    • http://darslaska.org/ckfinder/userfiles/files/10815193967.pdfIn PDF document text
    • http://thanhcongtechtra.com/upload/files/gepure.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/rubizixijotagim.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/52381369966.pdfIn PDF document text
    • https://vnsteeldetailing.com/UserFiles/files/gopibebalesarosafin.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/woleg.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles/file/16882544330.pdfIn PDF document text
    • https://akconta.com/uploads/files/18323768914.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/kunex.pdfIn PDF document text
    • http://another-partner.morefriendship.com/upload/files/61122685990.pdfIn PDF document text
    • http://daehwa.info/uploaded/file/gulek.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/juriribeg.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/tivebez.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/keradov.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/xupus.pdfIn PDF document text
    • http://d-a-s.cn/userfiles/file/8209320826.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/nogaxidetisuwuvi.pdfIn PDF document text
    • http://ahnil.com/userData/board/file/11168286291.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/29102323840.pdfIn PDF document text
    • http://52963566.com/upload/file/202109101649310138.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=good+movie+app+for+firestickPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d1aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BC 18560 bytes
SHA-256: 1de1e9258ce73c44871ec30e9922262f118326f13933b875111a31180b403c3f
font_02_sfnt_off00011a34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A34 10828 bytes
SHA-256: fd54da2e0fd26e267dc2879e2ed308d1ff18ef5ee50f02ad396554863f7454c6