Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e1d961b7ba40962…

MALICIOUS

PDF

75.0 KB Created: 2021-10-04 19:26:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fbb5cb368e185a1b5c809c572df6b5ac SHA-1: 02cdd2bc6e97ac2b4ed4433762026efff3c584e8 SHA-256: 3e1d961b7ba4096238a12b53a22286f522b90195230c00f919866d5d224c1cb1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of external URI heuristics and link farm indicators further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ketchas.ru/uplcv?utm_term=book+of+proof+3rd+edition+pdf PDF link annotation
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/2ee19aa89754b862c79df23a5be52ddb/54452848544.pdfIn PDF document text
    • http://askaudit.ru/price/99568106300.pdfIn PDF document text
    • http://apicn.net/upload/files/bokiwuxoxujofuriso.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/33291161340.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/gitikujiziwupevakim.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/32256028065.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/nipinokamuduwetufumudev.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/zerajubezisudilulom.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/bejokabewujilazubili.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/jolaxogoluzeju.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/mewuledotowadumoxip.pdfIn PDF document text
    • http://xinxinhouseware.com/uploadfile/files/ledogimukiroxirisanuzis.pdfIn PDF document text
    • http://codienlanhtrangia.com/Images_upload/files/90182015480.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/30173263944.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/lewoxabulakulafadab.pdfIn PDF document text
    • https://beldapromosyon.com/calisma2/files/uploads/47054605705.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327de4480d6---98078444041.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/21425411810.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/0a2ba40b761acc05f4292b01f34e1afb/81227187824.pdfIn PDF document text
    • https://learnrkbin.jugalbandiresearch.com/ckfinder/userfiles/files/subiwunene.pdfIn PDF document text
    • http://tai-group.com/upload/files/gemumakapekizekudokabam.pdfIn PDF document text
    • https://bank-kredit.at/ckfinder/userfiles/files/bapepajotajudoda.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/27580131180.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_off0000bd91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD91 19128 bytes
SHA-256: 872e489801a031bb3e3ad065f5a91f202ef125714b0cf0082b30c8507051706a
font_01_sfnt_off0000eef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF2 10432 bytes
SHA-256: 7b1ccf3b30a03c6b3753e87d068f230759b1d57cc402da60ddb682f81972fbde
font_02_sfnt_off000106bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1