Malicious PDF — malware analysis report

Static analysis result for SHA-256 21736d26a953730f…

MALICIOUS

PDF

88.3 KB Created: 2021-06-27 05:03:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: df81466c00a75330ad76f189b7b50279 SHA-1: fb0450acb6bd458b30d1f944f1de4c8828afb8e0 SHA-256: 21736d26a953730f2d5358ffaf71dbd907ca23e79e4e0210f7bebbe71b93296e
156 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. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress uploads and disposable hosting sites. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to facilitate redirection, hence the T1059.007 technique is included.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=radio+frequency+identification+technology+pdf
    • http://ahchala.com/img/file/mixusivajiguxegalavakumig.pdf
    • http://studiotrusso.it/userfiles/files/28465309543.pdf
    • https://ltanimalpark.com/wp-content/plugins/super-forms/uploads/php/files/921ebb7c01016c0a50428395b11b1a51/jobepeku.pdf
    • http://kistours.hu/userfiles/file/poxebitefevofa.pdf
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/g705a6f0enpl4tvhjf9gssvv35/17373037922.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16091f2dc34993---fomebomusexubifefixivizem.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb3ff43da5---numazudilopixuso.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/d67b6ad0e3b170b4a1311aba461c8d62/38948535952.pdf
    • http://biotledlight.com/userfiles/file///49177803607.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/ml7o1gm0a21tu9khe2ibclit52/55079166079.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b836e6a6097---lipoduxojamewurapabatitip.pdf
    • http://fongyoskert.hu/userfiles/files/dagupumolaxexasadodane.pdf
    • https://dcmheavyequipment.com/admin/images/file/pujuxuponorozibitetefik.pdf
    • http://chinajessie.com/seadata/data/uploads/img/file/162355407165.pdf
    • http://ristoranteibucanieri.it/userfiles/files/saveginigasevijod.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/3c8951e9b8513f86797321ba026d722a/49320899740.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/ba7141d0eb097c0d290488d646a7b27c/gotobonazejowepuranevone.pdf
    • https://hanyauntuktesting.com/contents//files/68662654247.pdf
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/8sfp34gq3ob5g1ogh2n52ihs46/makefulosomupilodisubij.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a696c596af8---92057999736.pdf
    • http://firegallery.ru/img/upload/88421715061.pdf
    • http://benhvienlaptop.biz/userfiles/file/63596482377.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160a1639a40c21---7274572301.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce0a0d9da8---guxegigotowagiwoti.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_off0000f7ee.bin
7042b8f8983b95acfda392bb2851e4ceb16465bd1d9c7e19171da9655e134fbe
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EE 11136 bytes
font_01_sfnt_off0001115a.bin
9d317824e1ed19be3fca9faa4502affaa15e9358fdce5a87bafda6dd15d48561
pdf-font-stream PDF embedded font (sfnt) at offset 0x1115A 16452 bytes
font_02_sfnt_off00013bef.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BEF 16792 bytes