Malicious PDF — malware analysis report

Static analysis result for SHA-256 2aeaa465b53df8a7…

MALICIOUS

PDF

77.6 KB Created: 2021-09-08 07:08:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 155963ee66cb0beeb8cd47fd32ddfdd5 SHA-1: c1b4e4537b14bb94102b36180df658e94cbcc9b5 SHA-256: 2aeaa465b53df8a7a641e27e6232edab762bb4643f42e0512cccc73d0b323cb2
96 Risk Score

Malware Insights

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

The PDF contains a link farm designed to redirect users to various websites, many of which host further PDF files. The ML classifier strongly indicated maliciousness, and the presence of multiple compromised CMS upload links suggests a pattern of distributing malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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://sghscsjamarai.org/guruhargobind/userfiles/file/fuvupavuba.pdf In PDF document text
    • http://jikaramen.com/uploads/files/72406336018.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/b04edc0f60463f92bf5a8cd16d2fd93a/dekisux.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/nigiwunonudusokonivumumow.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608c902058ec5---61633846686.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/6cddc95dde690e9d0689be98fa4ee473/19528815296.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/6991c25453273029a58d543c58224625/57583541613.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/61887172538.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/1da53e13bf5aed7ff9ba6f6a1914e4a5/16684572370.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/1cafaca48387abe3232c6a8cbc58ff58/53255506980.pdfIn PDF document text
    • https://sinhadventure.com/uploads/file/nujagerogudofulonasuwilug.pdfIn PDF document text
    • https://stvorki.ru/files/file/92105660794.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210803_66E34E0E3013262A.pdfIn PDF document text
    • http://hosteleriayvending.com//ckfinder/userfiles/files/roxaduberubupekatinid.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/jemusivitebirijim.pdfIn PDF document text
    • https://pastelbuilders.com/userfiles/file/jinijakipekitasir.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/11724798205.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607749f786258---34381209271.pdfIn PDF document text
    • https://impeka.lt/components/com_mijoshop/opencart/image/data/files/ketiloni.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/9615a3b6afcbf04088c9647ed8559047/tisosi.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090d581ed301---bibejubesinafojaxosumibim.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085279d7b87a---banude.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160768fa075039---56068606655.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=pdf+to+word+programa+onlinePDF 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_off0000cc09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e420.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE420 10760 bytes
SHA-256: 83257f2b4a6d06e4bbd01a0f00e847af379c6dd2ba864fb8878f95b2c5cb9760
font_02_sfnt_off0000fca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA6 17608 bytes
SHA-256: 2955ce9d0804d923b2e4d374123e70f845530c7fb3d66d974aafa3f9ab87df01