Malicious PDF — malware analysis report

Static analysis result for SHA-256 fffb378fab5c2bc1…

MALICIOUS

PDF

73.9 KB Created: 2021-09-28 18:09:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 37a94b7a19155dbac68c663f2e1fa3f9 SHA-1: bb2f1d70b68057df7df491a000dd167c979196aa SHA-256: fffb378fab5c2bc1b88be39ff328db2708edf3ce4502c6b7bfc61ea97f6be250
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm designed to trick users into downloading software, as indicated by the URL containing 'free download nitro pro'. The presence of multiple URLs pointing to compromised CMS uploads and disposable hosting suggests a phishing or malware distribution attempt. ClamAV detection and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://pistant.ru/uplcv?utm_term=free+download+nitro+pro+11+full+version+with+crack+64+bit PDF link annotation
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd01a2afae---69003071688.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/86638838080.pdfIn PDF document text
    • https://htcpost.vn/vietpost.vn/img_content/file/mekopenawejunuzi.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/4907720413.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146278bbc723---65403242668.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/64743259840.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/97469713500.pdfIn PDF document text
    • https://tamm.be/_files/file/butixotesewisujob.pdfIn PDF document text
    • http://mmsmarin.com/imgimage/file/gisidixerilonakenidurizi.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/fufizejuk.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/kitalezumapajuf.pdfIn PDF document text
    • https://invision.buzyhub.com/files/suzosabudizukogakox.pdfIn PDF document text
    • http://wagnerpc.com/userfiles/files/24220368988.pdfIn PDF document text
    • http://seatraveltx.com/uploads/files/15978553681.pdfIn PDF document text
    • http://gardens-spa.com/user_pict/file/pinegaxewitugejifazu.pdfIn PDF document text
    • http://energy-labels.com/userfiles/file/suxajetajarijeseworaxi.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/momenexevavevaxetipojaji.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614bbcd79f9e0---muzanabawagowegiximo.pdfIn PDF document text
    • https://cytairtool.com/test/userfiles/file/20210911_09b5b.pdfIn PDF document text
    • https://www.creativetalentnetwork.com/ckfinder/userfiles/files/sonoget.pdfIn PDF document text
    • http://kxqcgs.com/filespath/files/20210912062606.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/kolejujip.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210916_19949FF8839B1755.pdfIn PDF document text
    • 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_off0000b627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB627 18016 bytes
SHA-256: 4183cf07e1bf1b3024aa69d3e2736f3866090b4e6b499286672a950fee37e9ab
font_01_sfnt_off0000e460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE460 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fc77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC77 11476 bytes
SHA-256: 499b12b3d00b2d2244392a98c81ffa87b13d13679eacf2e80ce081a1fb86634c