Malicious PDF — malware analysis report

Static analysis result for SHA-256 3799931ff9aa7029…

MALICIOUS

PDF

70.3 KB Created: 2021-09-14 04:27:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 711092dccb41c0c16538a16ecb071a64 SHA-1: c227a174e7acf04bc919cbce009b6c8ef9b855dc SHA-256: 3799931ff9aa70290b514b2f314eaded97dab093c73f8c1cafc7f2536732be73
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs pointing to various domains, many of which are configured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to obscure the true malicious destination. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://philabc.ru/uplcv?utm_term=minecraft+latest+update+apk PDF link annotation
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/1425dd6a399baf79cea18735d4998404/vimejitisiwepane.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/xejawas.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/xotanopifosavov.pdfIn PDF document text
    • http://itemclinicchina.com/ckupload/files/21849160221.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/budujonijetew.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/96349321225.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613dc9194ae21---59424439278.pdfIn PDF document text
    • https://pensionradvanice.cz/res/file/tipegixigazobiweso.pdfIn PDF document text
    • https://auto826.vnpec.xyz/uploads/files/4986739763.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/fipiwirevopodegolosuti.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/xasuvujaxunolupowime.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/midonufebetovisufe.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///sonulepelaruguzatokeriki.pdfIn PDF document text
    • https://szallas-karpatalja.com/upload/15334710044.pdfIn PDF document text
    • http://888chji.com/userfiles/files/getup.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/xasum.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/belebujizigojebopipuzor.pdfIn PDF document text
    • http://wadsoda.com/UserFiles/File/38758124650.pdfIn PDF document text
    • https://termoformat.md/img/files/97600117710.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/jereziz.pdfIn PDF document text
    • http://altus.pl/userfiles/file/58556092624.pdfIn PDF document text
    • http://quinta.cl/upload/files/tanerujasetewol.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/74012580598.pdfIn PDF document text
    • http://purepoem.com/resource/docContentImg/file/2021-09-10/1bfd0eda07a9558d0ccbe66e921b316d.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_off0000b523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB523 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD35 15060 bytes
SHA-256: 74ca226ddae9cee1f41bcea66c5dc62d5dc182b4e7f9700f999a41c782d2069b
font_02_sfnt_off0000f300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF300 10676 bytes
SHA-256: 7b5266cc4a9abcc1577a1a79bd9d9856220b41837f2ebdaec1f599fc8c7e8678