Malicious PDF — malware analysis report

Static analysis result for SHA-256 49528f1a386a07cf…

MALICIOUS

PDF

98.0 KB Created: 2021-06-25 12:35:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 93050adaa33b0e500618e46db5d1cdbd SHA-1: 65da36812014399da90160b8f9b852ed6e3ba01a SHA-256: 49528f1a386a07cf5ee950919b0821466cd570db0bac9bf9fcf1319c474cef15
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous external URIs and link farm indicators suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://akvaguru.hu/user/file/75703849998.pdf In PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/36258661197.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160790d1e83e74---14115892298.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef13ae4bf9---73926693998.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd596de0c2---1025375511.pdfIn PDF document text
    • http://trungnguyenjsc.vn/uploads/image/files/11607704309.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/9fea50eeb2459942a8b613d8d007beaf/lelifazodimod.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7d9d09513---98063407485.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/dutasuxerawomolole.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/26129248937.pdfIn PDF document text
    • https://spacio.hk/attachment/file/4811354852.pdfIn PDF document text
    • https://cooperspick.com/files/badusaxoxevupetijabi.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/b0c782db594116fa239e36ee1c388b7b/farunekusibi.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e2c538d59---41304030496.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/c0v1s213ejnq17am2a1f1bhj94/33786966693.pdfIn PDF document text
    • http://eau-msu.ru/ckfinder/userfiles/files/gadunewaniwemopibada.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=pokemon+fusion+gba+rom+downloadPDF 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_off0001188c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1188C 18156 bytes
SHA-256: cf1ae6505d04150bca060464fd47eb0af469c067c1d02869fded7071e44c629d
font_01_sfnt_off0001480a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1480A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16021 11016 bytes
SHA-256: a3d3b25f839182850f02b17e22225939ac0109df3905b00e4a2e8c58753215de