Malicious PDF — malware analysis report

Static analysis result for SHA-256 5234a8de1c5b8c7d…

MALICIOUS

PDF

74.4 KB Created: 2021-09-25 04:10:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c422d1113db2e5a1fb3e5a44219dba2 SHA-1: beac5a34fae15a7d53b1135f769dfbe8606fe77e SHA-256: 5234a8de1c5b8c7dba3a5984838c4d0f9138213ba146b4f7971baf83096a36c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised CMS uploads, suggesting it's part of a link farm designed to redirect users to potentially malicious sites. The PDF structure and embedded links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=programas+para+descargar+musica+en+un+android
    • https://topclassgardening.nl/images/file/30593974784.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614232efb81df---57761211511.pdf
    • http://ibshop.gr/uploads/_uploads/files/sagipegegolopumaseka.pdf
    • http://elektromig.pl/userfiles/file/xetelawuma.pdf
    • http://alltimescare.com/attachment/files/durifelidavanuretanur.pdf
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/jemubixolubamo.pdf
    • https://ratosatu.com/contents/files/webewasotejefasegibanide.pdf
    • http://haohanlegend.com/Uploadfiles/files/bapesunesiguxil.pdf
    • http://market-oborudovanie.ru/upload/file/kapesegelepeme.pdf
    • http://muszempilla.com/files/file/9571481992.pdf
    • http://mega-gold.com/userfiles/files/72136243713.pdf
    • http://qianxi.cn/filespath/files/20210910172212.pdf
    • https://kysig.com/app/webroot/userfiles/files/nisijuzugajowif.pdf
    • http://everestlodgelukla.com/userfiles/file/15816892927.pdf
    • http://artemon.nl/userfiles/file/xivigujedowozo.pdf
    • http://www.euro-fly.eu/userfiles/files/xifenevosose.pdf
    • https://dimensioninteractive.com/WYSIWYGImage/file/25057868721.pdf
    • http://kaupa.cz/userfiles/file/mijuginawijexozejo.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/c84f0b5f95fff27b62e26e2402cf8015/89123677881.pdf
    • http://energywork.pl/userfiles/file/xutenep.pdf
    • http://dentalweek.eu/userfiles/files/fasawuj.pdf
    • https://skvely-kup.cz/files/file/44617409499.pdf
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/jolizejafefiditoloxu.pdf
    • https://niboparis.com/upload/fckeditor/file/1631475025_1.pdf
    • https://kawanmto.info/contents/files/52249225044.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8aecb10e6---navebadopubojaruledasuvuf.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ba8e.bin
c54d84be53e206b923e1b9f6428c8db8f08b0b93c5187c1927f4a16326391d88
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA8E 17732 bytes
font_01_sfnt_off0000e886.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE886 16792 bytes
font_02_sfnt_off0001009d.bin
3b8348a0bea51a2c50ab2058c336f788a08086f9f8a865fa1fed7ccea8b95a77
pdf-font-stream PDF embedded font (sfnt) at offset 0x1009D 10816 bytes