Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7c623aa3ed86210…

MALICIOUS

PDF

70.1 KB Created: 2021-10-01 07:04:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 831e6f7d4648e4e6a48799e76d51c4c3 SHA-1: 785324eef3ca5ca03752cf6b68fb39497317168a SHA-256: a7c623aa3ed862109a5def77a534616b29ef18249ef493cddc6365d36c6a3276
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to potentially compromised WordPress sites. The primary purpose appears to be redirecting users to malicious content, likely for phishing or malware distribution, leveraging compromised CMS uploads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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 http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143afccc25cf---dasanoxap.pdf In PDF document text
    • http://pspectr.ru/userfiles/file/bugisuninenizawilodutuzi.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/161565113cdf32---18502761959.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/26814347093.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/75557495711.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/kolofupisagazux.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/69901160721.pdfIn PDF document text
    • http://hstechno.com/userData/ebizro_board/file/zudetipot.pdfIn PDF document text
    • https://skatrip.com/basefile/skatripcom/files/15943054156.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/21000060632.pdfIn PDF document text
    • http://1855-4080.com/userfiles/file/58753844943.pdfIn PDF document text
    • https://12shio3.com/contents/files/vazotufiliz.pdfIn PDF document text
    • https://floridahouselottery.com/test/userfiles/file/manegenedave.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1614256871863e---pozijipuvab.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/safezojovoves.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140e39088f6c---sadipezevobilesawuva.pdfIn PDF document text
    • http://dmkaudit.sk/101/upload/file/45275049339.pdfIn PDF document text
    • https://verticala.ro/images/userfiles/13780468609.pdfIn PDF document text
    • http://highspiritsmusic.com/ckfinder/userfiles/files/gapovugapunu.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/jifawut.pdfIn PDF document text
    • http://kvrhousing.com/uploads/wopukomexizipofow.pdfIn PDF document text
    • http://simpelms.nl/userfiles/files/zulatunanakizejalarodeli.pdfIn PDF document text
    • http://zimmerei-possert.at/piwerosikeraruzevelikumas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=explain+the+lower+atomic+radius+of+ga+as+compared+to+alPDF link annotation
    • 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_off0000b3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DD 11340 bytes
SHA-256: cb4e0b16599860fce58bf5f5ef1ad735d5b42e95de6af171b8c5d9bd1a8826fb
font_01_sfnt_off0000ce37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE37 16724 bytes
SHA-256: 8669389c609a95c5fa6e82defead7948083bc996b683e6773e00f15217247a99
font_02_sfnt_off0000f969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF969 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1