Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9991769ff832738…

MALICIOUS

PDF

83.9 KB Created: 2021-09-23 23:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 85d27333b83aa935f89d39a0bac446a6 SHA-1: caaf770eb702436256032a27f5ae6938ee745545 SHA-256: a9991769ff8327388f309bde62a840041f701ce6e8423e8225c90d69747f1b9f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to lure users through deceptive links, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://elosc.com/upFile/file///ITX202109141109471923.pdf In PDF document text
    • https://atrax.eu/userfiles/file/tidaboburikadi.pdfIn PDF document text
    • https://fivetc.vn/uploads/files/60836980249.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/fedunesoguwemogolerimad.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149ce188d799---bunakujilud.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/nugefevada.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1614a046501b0a---fixavaf.pdfIn PDF document text
    • https://aquarell.ro/userfiles/file/zapemelupimafod.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/84271616108.pdfIn PDF document text
    • http://freeorden.com/media/file/faxilanoxim.pdfIn PDF document text
    • https://raselapp.com/userfiles/file/78341043171.pdfIn PDF document text
    • https://thuhuonglacquer.com/uploads/news_file/fabomeganijifibadu.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/63592963567.pdfIn PDF document text
    • https://granitnet.hu/editor_up/korevexanuxowamodelugar.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a284d67b43---kerojuzinavadikenajodara.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///dawazug.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/53142708175.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/xesenaxukawebodo.pdfIn PDF document text
    • http://ulv-fogger.ru/d/files/difunib.pdfIn PDF document text
    • http://air-ned.com/uploads/files/79552713270.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/42080076024.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=vigo+video+app+androidPDF 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_off0000e6e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E6 10288 bytes
SHA-256: cdf067240b30883590d51ae91818a872224486f5bf92acffd4c1ef26844da636
font_01_sfnt_off0000fdef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11601 17332 bytes
SHA-256: a3869d75eacaa111304f733974f8a167a0d10128e00611f01f98d598b1837bfe