Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a24bd3cb7f2dca4…

MALICIOUS

PDF

79.4 KB Created: 2021-09-08 23:26:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 56b797938ace3d95c62ccd2536d54553 SHA-1: 3f6cb28a58dc3c3c9e9752211cbf18ecd4245465 SHA-256: 9a24bd3cb7f2dca419df238664f860d1ecb3ff1f71a5f331b761e4a1fa2aea2b
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting domains. The primary purpose appears to be redirecting users to external URLs, likely for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://coretry.ru/uplcv?utm_term=4+letter+words+with+k+and+v PDF link annotation
    • http://szolnokepul.hu/userfiles/file/53178772612.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/pukonuropuserogewud.pdfIn PDF document text
    • http://www.jasolasia.com/image/upload/File/fisiduzuvinepum.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130811547c6e---dizalelobum.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134ae869876d---72138956240.pdfIn PDF document text
    • http://nguyenxuanhuong.com/upload/files/12872811803.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16130900ba9d40---bawoset.pdfIn PDF document text
    • http://packamate.com/userfiles/fuwisij.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161366667635fa---pilopotuxedokijevevorosez.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2aee8fc5b---rifibajewomoj.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134bcef6066c---kulojorazujene.pdfIn PDF document text
    • http://liily.jp/upload/file/20210906181226.pdfIn PDF document text
    • http://zehanbiopharma.com/upload/files/fisula.pdfIn PDF document text
    • http://ssatripoli.org/userfiles/file/walobidisakido.pdfIn PDF document text
    • http://shimamura-mail-order.com/userfiles/file/74296961776.pdfIn PDF document text
    • https://transport.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/50237092506.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210906_021415.pdfIn PDF document text
    • http://ajmason.com/admin/ckfinder/userfiles/files/75991330646.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210904160008030.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/29411494436.pdfIn PDF document text
    • 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_off0000d1a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A4 10568 bytes
SHA-256: 3b134184c4c6eb9694288cd3cb87d551af31d5959a3e628c489fcc859317b1dd
font_01_sfnt_off0000e9c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000101d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D6 18140 bytes
SHA-256: af93e901bc438246d3cdc570e186d354070b2b5b7b552bdd6cfe7a11918e22a1