Malicious PDF — malware analysis report

Static analysis result for SHA-256 b16b632df8fc8cf6…

MALICIOUS

PDF

68.2 KB Created: 2021-10-03 02:54:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 648a8f73995f84a34ac72eaedebf738b SHA-1: 36b9fbbef6b763a4c4e6646dc40ee7801be75ec1 SHA-256: b16b632df8fc8cf64a9da79f2480173a62411fd3ba2c92f2ab60896ccddcdd2a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to various domains, suggesting it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, indicating a potential phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://liantoong.com/archive/upload/files/2903906448.pdf In PDF document text
    • http://www.hkrns.org.hk/ckfinder/userfiles/files/27439464892.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16137e07a6a6ec---7077181943.pdfIn PDF document text
    • http://mrs724.ir/basefile/drtiketcom/files/riwopawud.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/kidige.pdfIn PDF document text
    • http://mabifitness.it/userfiles/files/zefadov.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210928163284790682.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/pumud.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/20191238871.pdfIn PDF document text
    • http://montereypark.kopanramen.com/uploads/files/silumazewepaz.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/lomesobubopuworeju.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/sujajibojegadowazitidur.pdfIn PDF document text
    • http://seattleteriyaki3.com/uploads/files/tudikisanuwisekowe.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/62048087344.pdfIn PDF document text
    • http://liderzy.natura2000.pl/imgturysta/files/93906213831.pdfIn PDF document text
    • https://travelone.ae/userfiles/files/xekazavoxima.pdfIn PDF document text
    • https://cupanghitam.com/contents/files/5489263908.pdfIn PDF document text
    • http://123flower.doweb.kr/upload/files/33049963985.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/sebinizi.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161391e6edd541---tunususawumoxi.pdfIn PDF document text
    • https://blsautomation.com/ckfinder/userfiles/files/mugizamaluwivabulokogi.pdfIn PDF document text
    • https://njshore.drinkpoint.com/uploads/files/96189046460.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/21/39274315337.pdfIn PDF document text
    • http://tramtronbetong.com/uploads/userfiles/file/jixawobesagiwewi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=piv+sex+meaningPDF 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_off0000ae3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE3C 15236 bytes
SHA-256: a36ea2e191b4a16694ea98810cced178ae780959b0c9ef893c1110e04c9e53be
font_01_sfnt_off0000d47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47B 10256 bytes
SHA-256: 1fa850d62c19700f1699b565ce64efc2fa5ca960f36ff6b9137307f6fde6567c
font_02_sfnt_off0000eb8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1