Malicious PDF — malware analysis report

Static analysis result for SHA-256 21e114d45a8fa01b…

MALICIOUS

PDF

85.8 KB Created: 2021-09-14 08:53:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f7553ef20c76a39a5cb3b47e9ed12a48 SHA-1: 87a92aceb916cef8a49842dd9e12a37e5eb6c9e7 SHA-256: 21e114d45a8fa01b45fcc52230a01ccb97224336f8943ba694aac0c0ad01dbce
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one specifically identified as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. The presence of multiple unknown-reputation PDFs hosted on various domains further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/4696387d2e0df26ef0ca95d9ebd83a72/70268096075.pdf In PDF document text
    • http://studiosantese.eu/userfiles/files/7393831380.pdfIn PDF document text
    • https://bccphil.paramedix.biz/uploadfiles/file/varoli.pdfIn PDF document text
    • https://motecx.com/images/file/54999140935.pdfIn PDF document text
    • http://frickcontrols.com/uploads/files/77140067296.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/22981096966.pdfIn PDF document text
    • https://membermimpi.com/contents/files/53042092182.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/29690031151.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109112127472220.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/sowaremenejozofikudi.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dbefcddc93---diwigiwuvak.pdfIn PDF document text
    • https://www.vignolaweb.it/ckfinder/userfiles/files/23047656168.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/burujizorijibajajelamerim.pdfIn PDF document text
    • http://www.stemcellhairclinic.com/files/files/kowipana.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210903_D9ACC367991EBA93.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/25545508559.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210911_0A3D9B1893146D3C.pdfIn PDF document text
    • https://gtnet-engine.com/ckfinder/userfiles/files/67047314306.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/lamureda.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/58344266535.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/lunilimadizuwunibisut.pdfIn PDF document text
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/potazifa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=best+android+app+for+moviesPDF 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_off0000ec4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001045e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1045E 17216 bytes
SHA-256: 3ad64abaea1d3f523fe67c004070bcbfb2ea69e1d23d67572503deb56bc62cee
font_02_sfnt_off000130df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130DF 10732 bytes
SHA-256: d3b804d87a80816570e6bd3164edc54684f8a8d78e50f47078a7f90001515729