Malicious PDF — malware analysis report

Static analysis result for SHA-256 1899b87c0964d753…

MALICIOUS

PDF

87.9 KB Created: 2021-09-02 02:12:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 097a3889da2d0c5a7bc1d491c00ad422 SHA-1: 2e5123bf2bd126ef7f8348c493443d87d59d8e2c SHA-256: 1899b87c0964d7532eddbca33a03803f88ebdd0f821c9dfa4d34d5aeb5fea84e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to disposable hosting and compromised CMS upload storage, characteristic of a link farm used to obscure the final destination. The presence of 'urgency/deadline' language, though low-signal on its own, supports a phishing or social engineering pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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.
  • 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://mnlex.it/file/48754619912.pdf In PDF document text
    • https://akproauto.net/nbloom/fckuploads/file/43807632346.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/3346863610.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/55656982859.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/jubumelowowozo.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/27278000676.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/96925c42824b69b5abc40dee7621dc81/kumewinenatopasud.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/wuxediwopakifejuk.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/354a8bc03dd39ad06ca6d1861b75c862/70262613298.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/e944487f7ffa8f09a9a3993a3727524b/kikobewa.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/ca6ad1c2e5091ca7224a82282c5cb427/bozefezagufi.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/juzox.pdfIn PDF document text
    • http://beytarimcilik.com/admin/editor_resim/file/88888776054.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/kaxifisofawanejekitej.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/91b71a40d3457011d8ba394b3970b830/44419382282.pdfIn PDF document text
    • https://hagakure.by/upload/editor/files/53698441341.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/lilebofefesabilokuvodib.pdfIn PDF document text
    • http://staples1981.com/clients/b/ba/ba027a536d51c1d997ee76cae6dc9017/File/46623540137.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16107df22318e9---94077949582.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/74622733618.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160783711e84e6---jobago.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f38bf802ba---12240348337.pdfIn PDF document text
    • https://isleo.com/i_photos/file/2238687277.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-6-7/20210607132226859375.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=questions+are+the+answers+pdf+allan+peasePDF 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_off0000f103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF103 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001091a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091A 10840 bytes
SHA-256: a976251f1c8577210cb848f2b76ef98cd5df5d69f3f7387a8d883e05aa3ce43b
font_02_sfnt_off00012234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12234 17872 bytes
SHA-256: ffa9ada062ce64f873a04fb3bd0da7d857e9836c821eb15445db0f8541a88752