Malicious PDF — malware analysis report

Static analysis result for SHA-256 824511149fe38cce…

MALICIOUS

PDF

68.4 KB Created: 2021-09-25 00:10:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 6f1291adeafdf1a0891c8c0b9c5fa0b0 SHA-1: b5374b3632528cde991bcafe67af00617c0fda78 SHA-256: 824511149fe38cceb3ca3d7978d805854491abba0b8ad22652f80d7c557a4105
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The presence of embedded JavaScript and numerous external links, many pointing to compromised WordPress uploads and disposable hosting, strongly suggests a malicious intent. The ML classifier and ClamAV detection further corroborate this, flagging the PDF as malicious and a phishing trojan. The embedded JavaScript likely serves to execute malicious actions or redirect the user to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • 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 https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/50763670259.pdf In PDF document text
    • https://uleshuzatabc.hu/files/file/78144431763.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/27151618576.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1614935efe9acb---kanubinizuforijaxik.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/20256303210.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/kedigiwometuwibop.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-6/20210906060420873975.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/89703695592.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/kodururavatum.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/27578302781.pdfIn PDF document text
    • http://www.ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/dinozolijetobigi.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb9a1962dc---78245355454.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/161422ac16e078---jozokaxasowifak.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/fesapujowo.pdfIn PDF document text
    • http://dlastudenta.org/Upload/file/tanexopuxa.pdfIn PDF document text
    • http://boldogelet.hu/media/kemun.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/sumalopoj.pdfIn PDF document text
    • http://iact2001.com/userData/board/file/42476056067.pdfIn PDF document text
    • http://www.serenissimaservizi.com/files/59808450724.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/fifevuxakijebupigo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=du+screen+recorder+pro+apk+no+watermarkPDF 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_off0000ad53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD53 10816 bytes
SHA-256: 3eab7e91b56f6ac125bd9e9401f011b9501269c47be281b38e5622b65e1b0615
font_01_sfnt_off0000c65d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC65D 14720 bytes
SHA-256: b04c85c773d8988cd27a02e646eab53572493632d54d973e04cb785654f6d01e
font_02_sfnt_off0000ebc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1