Malicious PDF — malware analysis report

Static analysis result for SHA-256 83c1592c34a8d877…

MALICIOUS

PDF

83.7 KB Created: 2021-09-05 07:35:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b482106998b913b4dbe0fd0034935819 SHA-1: 60c13a604d58e3e9d3bde3b03503a6e46b91781a SHA-256: 83c1592c34a8d877a53e9cb4fceaf3c9c0ebb2d99eaff50a206b4d86a95701ae
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to various domains, many of which appear to be compromised WordPress sites used for hosting malicious files. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a pattern of using link farms on disposable hosting to distribute content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://crewmak.ru/uplcv?utm_term=pengertian+kemiskinan+pdf PDF link annotation
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/r7soa64pcab7ciljiop8spktmb/janibozeterutejikulalire.pdfIn PDF document text
    • http://vwtint.com/userData/board/file/waripamida.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7e6f25420---37919515293.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da824101563---20386818005.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/3pl3tqn9eog67hdumu7hld7dj4/89044949836.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/11268525969.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16094c2c27fc13---79522220136.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/gigerusizegekolivemiri.pdfIn PDF document text
    • http://bwlpsalisbury.com/uploads/files/lemokebivimumudorunujovo.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/rusivujut.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c54771ae5f7---fowenared.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/tafudigibejof.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/a11188bd028945b41621a70f48525795/92169804017.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/87907115669.pdfIn PDF document text
    • https://jeanmarcrobion.fr/userfiles/file/66600935428.pdfIn PDF document text
    • http://proart.by/media/file/82530543076.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/m2f9a1r9hjusnnlfkvi972d8p4/87480080407.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160e290dfedd68---53509503315.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/84990554485.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160ddb9c826829---wuvejawo.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16071a134eb121---49311967992.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/93185047359.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160738e4bc4add---53510029805.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/xojedukisamenut.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_off0000e38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE38F 10768 bytes
SHA-256: ffda2d5652aea168d1103bd0121fcea0653497c205ee21dd21a22badcc7b4977
font_01_sfnt_off0000fc24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC24 17560 bytes
SHA-256: 236379e74b2e82fbc4819c0e66d05439e450ee57c2b1755133bc47d827a2aab7
font_02_sfnt_off00012975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12975 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1