Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac691a12358bb7bb…

MALICIOUS

PDF

68.6 KB Created: 2021-09-26 15:01:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c061a172eb9b455edf4cac6652619261 SHA-1: e9d51509c231073ef0795be83c39caef976a2649 SHA-256: ac691a12358bb7bbf7d6d40c33b59e4e6d2f3b55f5f7c7059a673918f3ebfde1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm or redirection mechanism. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a high volume of links on potentially untrusted hosting, reinforcing the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9891

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://chistogood.ru/admin/ckfinder/userfiles/files/93698843787.pdf In PDF document text
    • https://srinivasagroup.com/ci/userfiles/files/sabovatixafidutukevuda.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/buremofuxepokinemakireji.pdfIn PDF document text
    • https://ans5680.preneed91.com/upload/files/18159642551.pdfIn PDF document text
    • http://ideviceplus.be/app/webroot/files/userfiles/files/nuraxeloxel.pdfIn PDF document text
    • http://delfosventures.net/userfiles/files/morikepixumel.pdfIn PDF document text
    • http://m2m2design.com/userfiles/66482790327.pdfIn PDF document text
    • http://aquatherm-graz.at/files/76397369560.pdfIn PDF document text
    • http://www.rupankar.com/fckimages/file/43641013715.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/ea1291e412f6d52878c373c5ffb55c42/85846450439.pdfIn PDF document text
    • http://dpkwi.org/userfiles/files/seriloxilotebinot.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/56384614524.pdfIn PDF document text
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/wimigox.pdfIn PDF document text
    • http://systempro.kr/userData/board/file/kerupimigugemalapunejalo.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/f52fb07b07d4006389e0833520789f8a/gugajutovoxuf.pdfIn PDF document text
    • https://nistd.in/userfiles/file/kesoxagigisinutibewobopos.pdfIn PDF document text
    • http://hopkim.vn/upload/files/zebera.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/jezisepunima.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/78846899636.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/15084939850.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/79808804170.pdfIn PDF document text
    • https://www.sophrologue-nimes.fr/upload/news/files/sobuwifazofage.pdfIn PDF document text
    • http://studiofapas.it/userfiles/files/3701591045.pdfIn PDF document text
    • https://dalyanestate.com/userfiles/file/56746116996.pdfIn PDF document text
    • http://personnelstrategies.net/userfiles/file/lisadigojogur.pdfIn PDF document text
    • https://aleemanschools.org/userfiles/file/7388121711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=live+stream+princess+bridePDF 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_off0000b0b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8CE 10672 bytes
SHA-256: 4c3d69e8e1c1ed16cc87b49b77416b78459a57c0b4be69cf48dca07d311f82bd
font_02_sfnt_off0000e10c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10C 14396 bytes
SHA-256: 2e95d467962b11ef572b4e1391a6cc1ccc6c63263cb08c10fc3acd2ba3a70f89