Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a03ba70823a26e3…

MALICIOUS

PDF

68.1 KB Created: 2021-09-25 06:38:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 45062f54d634ae6da8b2a0a849f66ff7 SHA-1: 16cd26a7190fcf5de71da5fbc705647926a596c2 SHA-256: 1a03ba70823a26e3bead1e9836a9214e328c2fc509935287a63f1ef4aca11ea6
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of external URIs and link farms points towards a phishing or initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 http://centrlita.ru/archive/image/file/5936878514.pdf In PDF document text
    • http://viquadro.com/userfiles/files/lapufudolidu.pdfIn PDF document text
    • http://bycongroup.com/UserFiles/file/legemunit.pdfIn PDF document text
    • http://studiostocchi.eu/userfiles/files/36518318857.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/ponixavunenikapoxok.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/67552181626.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16138e8f0b92e5---70097760571.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/vovosafomil.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/gapalizukub.pdfIn PDF document text
    • http://tatishev.ru/admin/ckfinder/userfiles/files/79572508205.pdfIn PDF document text
    • http://woodlander.sk/grafika/file/46843606801.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140bb3b23865---40333521758.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/2625f6e1d7d0da969a9ea246e53f109d/27382847211.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/19328554414.pdfIn PDF document text
    • https://sakkestadbil.no/userfiles/file/16867414638.pdfIn PDF document text
    • https://hanoihome.net/img_duhoc/files/lakopuwuge.pdfIn PDF document text
    • http://9262895.ru/ckfinder/userfiles/files/45132437510.pdfIn PDF document text
    • https://hoakhanh.vn/uploads/image/files/71488472178.pdfIn PDF document text
    • https://nic-irq.com/userfiles/files/wikefejawunuzax.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/danobijekifivofewo.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/33711681830.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/tiranalip.pdfIn PDF document text
    • http://mtcnx.com/upload/fckimagesfile/28394471366.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=grindr+for+android+apkPDF 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_off0000ad1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD1F 15284 bytes
SHA-256: 6196db9fd596c73dba5bfa53510107484d07ef7d252bdadd85da19a1f541f1cf
font_01_sfnt_off0000d45e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45E 10180 bytes
SHA-256: d66a0ca442dec9600875a0a66be344b5ac8c21510317ef9f9bc81a098f5ee9eb
font_02_sfnt_off0000eb34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1