Malicious PDF — malware analysis report

Static analysis result for SHA-256 77418a976c241ef4…

MALICIOUS

PDF

86.8 KB Created: 2021-09-15 04:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5894b95c013ff113f72894c9ff31274d SHA-1: b80664e594ffa428e9c59f5ccbc185bdd1cb627e SHA-256: 77418a976c241ef4c0a9dbcb8686360e20b49f37a08353abed82ab45e7eceda7
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or SEO manipulation tactic. The presence of embedded JavaScript, flagged by heuristics, indicates potential for malicious code execution. The ML classifier strongly suggests malicious intent, likely related to directing users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://coretry.ru/uplcv?utm_term=best+graphics+driving+games+for+android PDF link annotation
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/nexemesagi.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/615ebc16f9d75202cb7205e8afb0b6e6/rawopawudunesinubipuvije.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/26161028493.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/pilobareforikunowuti.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///pikomox.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/vekomudojekon.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/57053703600.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/70657dff1dfd2bc72040c39ddc9e45c0/96382958385.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/botoder.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/tefifeluju.pdfIn PDF document text
    • http://gidromall.ru/img/uploads/file/73606370602.pdfIn PDF document text
    • http://orthodoxnews.us/file/likazisabojukoba.pdfIn PDF document text
    • https://asken.as/bilder/file/86799179084.pdfIn PDF document text
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/59914873244.pdfIn PDF document text
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/27474807364.pdfIn PDF document text
    • https://ngusacdon.com/upload/files/niwewomuremenowojoxixax.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210907_1C9597D27617F7E0.pdfIn PDF document text
    • https://gastriklandsbf.se/UserFiles/files/33689020733.pdfIn PDF document text
    • https://tauthuy.vn/upload/files/lurasapexotisag.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/mopivozuvumakaxanizunari.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/texopanowebivedusigita.pdfIn PDF document text
    • http://bloodfaces.de/attachment/file/19287728748.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1613e008664610---66954518047.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/jizawubewodotiwanaxu.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_off0000efb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C3 16888 bytes
SHA-256: 369bdeffc3a9e4a116d2b5ece15e4d0ac86ae7a607358475f4c4c23f7e9d886f
font_02_sfnt_off00013347.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13347 11140 bytes
SHA-256: 66dd8ef42c88d329690de71047731938352b10b5fa8dde99c5c1429d23992334