Malicious PDF — malware analysis report

Static analysis result for SHA-256 911a1fd8d3d17106…

MALICIOUS

PDF

100.5 KB Created: 2021-07-06 12:34:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 393fe0080a768b348dab312fd6259543 SHA-1: 26b8c9a4ca36e1432d0cb6f3599bf55644cf2691 SHA-256: 911a1fd8d3d17106872cdb919c12ce25ac051e2f7e4af58a3ea523de9fb2a588
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous compromised websites, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The file's structure and numerous external links are consistent with a tactic to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609c805b9946e---dudofuxufonezumuzopejeju.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16086301194736---58742579547.pdf
    • http://sgyscom.com/upload_fck/file/2021-6-15/20210615014446988796.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/qvfirmhok9tglniukpdgimf26n/xoxizovumipufosakudixesa.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aba2676c46f---jonisetik.pdf
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/a8b06ad76930177506ebd5deead08c0a/41375092964.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608039009fa9b---39885022916.pdf
    • http://truhlarstvisollner.cz/data/file/zefuwu.pdf
    • https://monyetjoget.com/contents//files/38357757528.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608747fd75afe---81730809809.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/570s29up3q1slhpjsjhl0rhj38/bisozalajoxolofejiga.pdf
    • http://akpanlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59626022677.pdf
    • http://pensjonatagat.pl/userfiles/file/welosilaxuwajuropesovafod.pdf
    • http://ptairsupply.com/userfiles/file/53556321241.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/835a2794fdc423ccfd05d48afe45b0f8/48158928219.pdf
    • http://musorcentrum.hu/files/article/file/46955834450.pdf
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/2vb9ef0401vskp2jq66lhkvka1/46493498392.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/q8sqge93s165qoci04bsj0rist/39373580089.pdf
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b65b2980390---resibotesipovibifekopexif.pdf
    • http://abacusnancy.com/userfiles/file/buwupuropevopova.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1a7973fec9---vopobagukefajagupefadevun.pdf
    • http://firewheels.pe/userfiles/file/pasavud.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/33c8134def5f5d983b4430b12f55c3d9/16647500221.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=chemsheets+gcse+answers
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012560.bin
c6ce430d383c77862f3ff9623879085b4b0d1b1ad51561e33c405ef5bfcef076
pdf-font-stream PDF embedded font (sfnt) at offset 0x12560 18280 bytes
font_01_sfnt_off00015508.bin
e94e149b3459ea6e383d92bc59625036c4bf05f65574d8128e414f2c7bac5922
pdf-font-stream PDF embedded font (sfnt) at offset 0x15508 10536 bytes
font_02_sfnt_off00016cf9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16CF9 16792 bytes