Malicious PDF — malware analysis report

Static analysis result for SHA-256 1088823b4a69570f…

MALICIOUS

PDF

93.7 KB Created: 2021-07-13 18:33:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 81230806ba8b37d1faf97236d81049b6 SHA-1: 78528d58b0c71f00e03d40b1d3d3f6bcbacc4ae4 SHA-256: 1088823b4a69570fe8f0946910ecffe2077f794045afdc26a41ab4fb15ec838e
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to distribute further malicious content or phish users. The embedded URLs, while some are marked benign, contribute to the overall pattern of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://archinfo.ru/uploads/file/bewexefisukoxaj.pdf In PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606e804c3e667---91918663443.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/8593735309.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/dorovanulowifatiroruro.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160908aca501b9---xalinelutarotek.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/55620538711.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9a6c0b4e1---77964182095.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d79d6a2dd56---59361625495.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/jjj0934sc78ek5lt6vh9u1keu4/53674104257.pdfIn PDF document text
    • http://zulaikhatextile.com/userfiles/files/62605157982.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/45721779930.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16079e92c6c2fe---84046272420.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/6d967d370b1ec30b46ca6201e725d114/dowetivuvagivekuni.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef3edcfa2a---dujokenezetilewawu.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bf9151f1070---xefobo.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/axopivapudigakigudo.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160940bb1de416---20218242888.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16072d7a72d82e---86011992279.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/mokotara.pdfIn PDF document text
    • https://atlanticcompact.org/userfiles/files/safajuzibivor.pdfIn PDF document text
    • http://weingut-suppan.at/files/xusatutixejagukozikog.pdfIn PDF document text
    • https://inifd.london/uploads/file/67005172680.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/wuwafogafadejijumigufo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1843ad84ab---fajexuzotatim.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/6c661da1a77620d468e8463af116fec0/21812734445.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+reduce+side+chest+fatPDF 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_off00010ac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC1 17124 bytes
SHA-256: 9274772f1c0c853112406225992d1caa5b625aef5e5b3449fc876bae287f0362
font_01_sfnt_off00013756.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13756 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014f6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F6D 10600 bytes
SHA-256: c09841603274fa1daa4349d572a6ee45ff4b7e004ad09a2ad7614dc03eec9b22