Malicious PDF — malware analysis report

Static analysis result for SHA-256 c63323fd219f147b…

MALICIOUS

PDF

846.6 KB Created: 2021-07-08 03:27:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b899e4fca878233a115e10fdce7e5e92 SHA-1: 325f08a08014f18e40c1ade14b0ff780273ecb88 SHA-256: c63323fd219f147b6b4003da479d5248c69255c4188049e9bed14e3b8fe6739b
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and ML classifiers, exhibiting characteristics of a phishing lure. The PDF contains numerous links pointing to compromised CMS upload storage, suggesting it's part of a link farm designed to redirect users to malicious content. The presence of external URIs and SEO redirectors indicates an attempt to disguise the malicious destination and trick users into downloading the file under the pretext of a free download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5346

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.
  • 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://tourister.kr/userfiles/file/86231271130.pdf In PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd7acb4ab9---jinofobelivuva.pdfIn PDF document text
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/fuxexaxabule.pdfIn PDF document text
    • http://jirehenl.com/userfiles/file/160752358917.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2f37b146f---tojusub.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0f7852ec1---viviragokupelureb.pdfIn PDF document text
    • http://asianmosaicnyc.com/userfiles/file/dazebanevodan.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/9c15fc3200d976bd962c395edf5c4c22/tidumudaguzuronegumatereg.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/jezivivorusuzafa.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/27826dccdf4e32df76cc3c96f40fafe0/72860936909.pdfIn PDF document text
    • https://bczenekar.hu/files/file/nojimawevekezejelitobab.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a814b8a090c---89759192196.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607190a2c626a---kudadufotap.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/f9c305f7dec939195e90a7bc0d9103b2/83063247003.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/9e9fd4b5e0c9dcfb6794f053b47e2abf/69598293330.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160c6da2f9dea4---kirokotufivuwutamofefekax.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16077c2fdb134b---mozoxivolatima.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4a276b42d---88232471414.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/89833740089.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0a0d10f47---91528989546.pdfIn PDF document text
    • https://www.colours-of.com/wp-content/plugins/super-forms/uploads/php/files/1d9q0qnb3degnoq1i11pqu69vu/fusegemasag.pdfIn PDF document text
    • http://holycrossyouthministryasp.org/clients/f/fa/fa15eac34f6f8ef5a8ada011ffef1578/File/33412153757.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c96436e07b---63052932225.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=national+system+of+political+economy+pdfPDF 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_off000cc537.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC537 20204 bytes
SHA-256: 7bb246965517b64467b6e12734db09ebcbdd0a31824f6e1dc9e6e9faae48969f
font_01_sfnt_off000cf6d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF6D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000d0efa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0EFA 10772 bytes
SHA-256: 27dc5cbd520b4155e755c726dddd83af743d0bbc81945fa84f90c14c5e4e3a6e