Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f99ae186b858dbd…

MALICIOUS

PDF

75.7 KB Created: 2021-09-13 05:58:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: b974b49df439dc0afd8c92e9c6de2002 SHA-1: 7beeb11096ffd058debc27628fa73a8d54b84bed SHA-256: 1f99ae186b858dbd44cb7f16c284fab02b305d79ec07cd65bbf394c04407257a
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains embedded JavaScript and a link farm pointing to various PDF files hosted on potentially compromised websites. The heuristic 'SE_CALLBACK_LURE' indicates the document likely attempts to trick the user into calling a phone number, a common tactic in tech-support scams and callback phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 8

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nagakuratrading.com/js/upload/files/21249607335.pdf In PDF document text
    • https://polandpools.com/contents/files/vagus.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/57524585057.pdfIn PDF document text
    • http://aweibel.com/Photo/file/kedozemogobojelabonikusu.pdfIn PDF document text
    • https://www.campacinter.com/image/upload/File/6813412985.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/11169990805.pdfIn PDF document text
    • http://debten.net/UserFiles/File/perijugizubebedinoni.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210911171701091.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/71586941137.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/mozilimuza.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16132fc5288d5c---90839284344.pdfIn PDF document text
    • https://phoenixturkey.com/upload/ckfinder/files/ditinufabejuxejubexotaz.pdfIn PDF document text
    • http://superazs.ru/images/news/file/6605404041.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/88358104907.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/bajevigub.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d079b11fc---66234114848.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/31082349293.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131864ca140b---54353874849.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/52560525346.pdfIn PDF document text
    • http://a899.net/userfiles/file/18199881035.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=fundamentals+of+machine+component+design+5th+edition+solutions+manual+pdfPDF 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://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_off0000c7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7A2 17088 bytes
SHA-256: 094455d486a4a4e67c191f1c6eb164e268f110d8b25440d18cf5ac8d1411c473
font_01_sfnt_off0000f3b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B8 11180 bytes
SHA-256: c2ee3057d7c4c1d5c3ebc1713384a5505ed320edbf13515666d73422d02a2596
font_02_sfnt_off00010d7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1