Malicious PDF — malware analysis report

Static analysis result for SHA-256 63a15305fdee5eba…

MALICIOUS

PDF

79.3 KB Created: 2021-09-16 12:08:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 17924c321c0e29af4f86306f5a5f6bbf SHA-1: 93ecfb7266944b1d783b063ec8df006124de653d SHA-256: 63a15305fdee5ebac1c71728f27d2def94c3299329ede1b8aac7f9352d2304b5
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 link farms and potentially malicious content, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to redirect users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://studiotecnicoarduini.eu/userfiles/files/zezevezeziriwosikenema.pdf In PDF document text
    • http://ahkjt.com/upfile/file/memewofisavediboxiruxim.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109120024176499.pdfIn PDF document text
    • https://bayihoki99.com/contents/files/39993450460.pdfIn PDF document text
    • https://www.mppoa.cloudlinesystems.com/assets/ckfinder/userfiles/files/20221671646.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/woduromalujiwimujifupo.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/vigurodisagabajeku.pdfIn PDF document text
    • https://poulinstrapscan.com/userfiles/file/kuzije.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202109042136077373.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/kefuroxumi.pdfIn PDF document text
    • https://abhimaninteriors.com/ckfinder/userfiles/files/fajajanuvoz.pdfIn PDF document text
    • http://studiotravenzolo.it/userfiles/files/dizenuresamap.pdfIn PDF document text
    • https://biographiewerkstatt-singer.de/userfiles/file/silebut.pdfIn PDF document text
    • https://domilot.com/uploader/files/loberesuw.pdfIn PDF document text
    • https://perfecthospital.org/ckfinder/userfiles/files/55360879204.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/9229381600.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/6054533167.pdfIn PDF document text
    • http://www.luna1956.com/images/library/File/47612566122.pdfIn PDF document text
    • http://kesherisrael.com/uploadEditor/files/subiwijakosabexopevo.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/36817680587.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/44359631519.pdfIn PDF document text
    • https://ckv-siemreap.org/ckfinder/userfiles/files/worizazasovemafofuwezos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=ethical+decision+making+processPDF 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_off0000d401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD401 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC13 16372 bytes
SHA-256: 02c9954a8f6f1952bdb0a0257d8ee1949822bfe0b2543e9c6b0e43a0ea946922
font_02_sfnt_off0001166a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166A 11036 bytes
SHA-256: 3cd43ba4fc8fbad5786535be29ce630b17a13c37016728ed29cb3f1eb9a05f9c