Malicious PDF — malware analysis report

Static analysis result for SHA-256 888652bcd382115b…

MALICIOUS

PDF

82.5 KB Created: 2021-08-10 19:03:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9440b02d3b26091833d8423c6df74f90 SHA-1: d2de347ab30f5380486175da786bdf8471b15cf6 SHA-256: 888652bcd382115b125c4f6e553cc35fff81994fe8c1138825a6fc6e1122003c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to distribute traffic or host malicious files. The ML classifier strongly indicates maliciousness, and the presence of external URIs points towards an attempt to redirect the user to potentially harmful content. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious distribution or SEO poisoning campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://oniceh.ru/uplcv?utm_term=what+is+the+best+oral+contraceptive+for+pcos PDF link annotation
    • https://dcoderesearch.com/uploads/mezexokawuz.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/45621ca1792437a20523448e9d6b3a54/jarupurukukex.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/3041531182.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/nofesetubizisigu.pdfIn PDF document text
    • http://mashhadgardi724.ir/basefile/mashhadgardi724/files/xiwosemuwu.pdfIn PDF document text
    • https://www.varishastalari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb2c4a2b3e---kikebuj.pdfIn PDF document text
    • https://777mto.com/contents//files/51321380300.pdfIn PDF document text
    • https://rinducm1.com/contents//files/zezokisidulikefupab.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160841ab657403---vokikego.pdfIn PDF document text
    • http://asianaccounting.com/admin/fckeditor/userfiles/file/wakax.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/3sihoju61m9deuhd5uvni8e9te/kumifa.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/6d4506d03d19b9a249faf488b5cbd539/rubasojipebidojosuruku.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160e5c07628362---86948766497.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/2021052706170393909.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/23456946397.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/78789256236.pdfIn PDF document text
    • https://tekmaker.com/upload/files/gunedu.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/b3d07be58e4a279d9266e11bfda329be/kosizes.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a46ff444f87---xijogakefilo.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/4tvml1vc9emtvcpqi0sufkhlg2/60280650226.pdfIn PDF document text
    • https://mimpishio1bet.com/contents//files/wokufenaronipapinen.pdfIn PDF document text
    • http://cuhs1981.com/clients/8/82/82ca37c076ec4232796cb58ed009bb3a/File/runopisakob.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606e8ae30c6ea---82223774789.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/safph15v8vdldrgd6e3b9r2sr3/51672365365.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_off0000e005.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE005 10776 bytes
SHA-256: 2ea896b88d87057eaa32af4f01ee641ffaf80cc4cf4854d2c6781879e5cff46a
font_01_sfnt_off0000f895.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF895 16788 bytes
SHA-256: b874fee0401905b99d08e90160856385ec17ef6fba69e84b3283c83c2a98f383
font_02_sfnt_off00012403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12403 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1