Malicious PDF — malware analysis report

Static analysis result for SHA-256 79b0809640be98d0…

MALICIOUS

PDF

70.1 KB Created: 2021-09-28 09:43:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bcd443af0a994f9a43c58704612b7a89 SHA-1: 4f20a6e2ebe1b0b12906819df814d4e250b28be0 SHA-256: 79b0809640be98d023bbd6bdf480b2a9201baedbe87ce10ec878189879fbd843
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of external URI heuristics and link farm indicators further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://garglob.ru/uplcv?utm_term=free+tower+defense+games+android
    • http://tcsklife.com/filespath/files/20210918185443.pdf
    • https://12shio2.com/contents/files/pifetivoboliwebimo.pdf
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gulap.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614cf0b35b3e0---wipuzitizorilelogulogal.pdf
    • http://mabo-meccanica.eu/userfiles/files/14756659920.pdf
    • https://anfauglir.com/images/file/97276253094.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16134a513db043---dikunozokurid.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9fcd43ede---xukobetokesom.pdf
    • http://bigcool.net/webroot/img/files/31038233738.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613790867ad55---64096958287.pdf
    • http://fujieshubao.com/zk/UploadFile/file/2021090500545773499.pdf
    • http://architettoannalisatinelli.it/userfiles/files/33667304794.pdf
    • http://avandcie-automation.fr/ckfinder/userfiles/files/60569194336.pdf
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/94158db9799599ebaadae18f90662eb9/18015221157.pdf
    • https://ce-mi.pl/uploads/userfiles/files/56414581523.pdf
    • https://possamaiferramenta.it/uploads/file/konurasu.pdf
    • https://nbretail.com.vn/ckfinder/userfiles/files/vibivitex.pdf
    • https://cleanenergy.mn/uploads/files/xulubevamivibatogagef.pdf
    • https://pinkrali.com/calisma2/files/uploads/loguliso.pdf
    • http://wannawwannie.pl/userfiles/file/99352123581.pdf
    • http://finadev-groupe.com/userfiles/file/34300942411.pdf
    • http://philboyd.com/46111359470.pdf
    • http://jinistudy.com/_UploadFile/Images/file/7387172324.pdf
    • http://restokrat.info/userfiles/file/83226062993.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_off0000b366.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB366 16792 bytes
font_01_sfnt_off0000cb7d.bin
c2f0d30a09b3fc20b9dd1dab10127d9ef37667bb87a14bdf29cbefdcd2a128ab
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB7D 10716 bytes
font_02_sfnt_off0000e3ea.bin
ff5024c85b1d59805a4d4baa28afda9c35ed4091b597ba419521e1c6f69480fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3EA 15496 bytes