Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9b99ab1fe0dba7d…

MALICIOUS

PDF

75.3 KB Created: 2021-09-19 18:34:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0a25635c7ef7f70c10e1973517e9da91 SHA-1: 1aca16c7125a1d3d822404abf099fba361897754 SHA-256: d9b99ab1fe0dba7d23f22f8dba2397176c4c1dd8b5dfa96a0504dd1fc6d57fac
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely facilitates the redirection to these malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=convert+mp3+to+ogg+android PDF link annotation
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161415dde76442---56298407880.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/pijuvulelozuvupanowotawe.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210919_D4DB0D8138B0508C.pdfIn PDF document text
    • http://phukhoabacninh.com/images/files/pulofixarelexuve.pdfIn PDF document text
    • https://digitaluzaktanegitim.com/calisma2/files/uploads/rogovasebefodo.pdfIn PDF document text
    • http://gallery4walls.com/upload/editer/file/pufofofukixujanofezaf.pdfIn PDF document text
    • http://kingsfci.com/userfiles/file/16726446358.pdfIn PDF document text
    • https://lidiyageorgieva.com/ckfinder/userfiles/files/kimanoxagijogo.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/rokiju.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/muneludawimoraves.pdfIn PDF document text
    • http://faithleader.org/js/ckfinder/userfiles/files/77411138693.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/nawijag.pdfIn PDF document text
    • https://www.sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/lasimikimefozarofezow.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16140374072e7e---fixevopalomurubo.pdfIn PDF document text
    • http://spbi.cz/res/file/vejepusulivoginut.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/rimadozufitudenoku.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/ketepejesodo.pdfIn PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/98965580985.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/dodazezidifurefefawubopez.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/ghb4pbj704m3e8vp3m69459301/fedajovuve.pdfIn PDF document text
    • http://contelex.it/userfiles/files/81306195715.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_off0000b828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB828 10792 bytes
SHA-256: 06ddd1e1c39b97b3363bcec04bd015119a7b5a6bc524a8e30b5a916711da2239
font_01_sfnt_off0000d0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D1 21276 bytes
SHA-256: b0dac56b71f23f25c35efc17850a09dac6bf5815e1172102010039e06d698de9
font_02_sfnt_off000107cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1