Malicious PDF — malware analysis report

Static analysis result for SHA-256 4161a454c7e9ea4b…

MALICIOUS

PDF

90.0 KB Created: 2021-09-14 18:00:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6f8e9ee00ac38980b481159181144868 SHA-1: 6cba0b53dffe748c6917986551662c62e9b9e171 SHA-256: 4161a454c7e9ea4b1e774d982f962f43127f934056029c27d679430e95775404
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct hosts, likely for phishing or malware distribution. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure point towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://cosplay-expo.it/ckfinder/userfiles/files/6463119416.pdf In PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/161355fe11e346---27010244524.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/96516364765.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210913023113.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/moxapofofuju.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/xokinoliwokodavexogata.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/dunokojizuzupadap.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/82143037224.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/fidadejimeforepomotuzefi.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/jakixewanabokevekujusamap.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/gekawelitubokaruzipowig.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/85624123031.pdfIn PDF document text
    • https://agatanorek.com/files/file/pugakan.pdfIn PDF document text
    • https://asesoriagade.com/app/webroot/files/files/48238683993.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/59769171777.pdfIn PDF document text
    • http://calisnt.com/uploads/files/58926727654.pdfIn PDF document text
    • http://pinxedien.net/upload/files/sosidarumesidazizebiwanos.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/kunotabifumakopon.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/xekirijakopenaxusalemose.pdfIn PDF document text
    • http://freetourscadiz.com/ckfinder/userfiles/files/97167594253.pdfIn PDF document text
    • https://calprin.com/ckfinder/userfiles/files/1285786839.pdfIn PDF document text
    • https://spotiverify.com/ci/userfiles/files/kemokimutoribepiliz.pdfIn PDF document text
    • http://vectorma.ru/uploads/assets/file/15722332179.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/92664995169.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+transfer+data+between+android+phonesPDF 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_off0000fa24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001123b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123B 10764 bytes
SHA-256: c8bcd4e070509a701fe76e4f721ae2fe5990beb76e60fe94e5d9e31dcdf11cff
font_02_sfnt_off00012ab7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AB7 18156 bytes
SHA-256: ac84e1868d115a5556ed50a6ad7cf4f27d9d65a0956e5c8e69863f0406f51e4c