Malicious PDF — malware analysis report

Static analysis result for SHA-256 4458cd7bfcc558a3…

MALICIOUS

PDF

85.6 KB Created: 2021-07-13 20:08:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a17218e966bb7f899e34d3b834fb93b4 SHA-1: a11da092377f95e2536a4664d5cf5813b8fdd363 SHA-256: 4458cd7bfcc558a36a85efc8ede5457ad9d4d0e75cce1dcb01989ee8e758c197
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload sites and other potentially malicious domains. The PDF structure itself appears to be a lure, likely intended to exploit vulnerabilities or trick users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://mwflower.com/upimagesfile///44287936537.pdf
    • http://systemsbiology.at/uploads/assets/file/funupazarukasibasudo.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc2fe34a87---10005328233.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16080fc232f1a8---55954411220.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f73ced711---42829527111.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ef1fa8d54---kuzebirowiwoxofuvakigijuf.pdf
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16075084034ef2---80013363344.pdf
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/n5bn0akpkphp9gjp2ad8j8ppm3/33968858328.pdf
    • https://lesfeesdelhetre.fr/upload/files/9042539274.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e4a60dae8---72802239063.pdf
    • https://adepotcustom.com/UploadFiles/file/20210514151234178.pdf
    • https://peptidturkiye.com/ckfinder/userfiles/files/zoxedibugilotosazijevoxip.pdf
    • https://congchunghadong.com/uploads/files/zawudosugadatulebutu.pdf
    • https://10glazsikeyrosa.ru/file/61965909961.pdf
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/i75df7rf6r8ipg6rhb2tfdls47/favamodebigiwivudamaji.pdf
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/bcc5f5c37c7f5e28da321ad27429adc3/mumeronafolijabidav.pdf
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/fa59b88a54505a0bedd1e3a31f369870/mubamavufojiradelupete.pdf
    • https://serviceservice.eu/userfiles/file/welubakirep.pdf
    • http://ducthoaudio.com/upload/files/xodevenufigaxokilufegi.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8cec096de---7038759330.pdf
    • http://4darchitecture.org/img/all/lisatigijaxuwufixu.pdf
    • http://anhbanglaw.com/userfiles/file/pixisofekaxajinipuxafowo.pdf
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/14797512966.pdf
    • http://biomehl.com/images/content/files/8659093160.pdf
    • http://bajcsidavidfoto.com/_user/file/memivozezezomanolufizid.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=assistive+devices+program+manual
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/a3f1a20317a654d10788dd8d38ce8265/12186496686.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_off0000ec39.bin
49b046d9cff38a6bb981a929d9452d583c62a41bc5d1341db5d17b6e9300f4f7
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC39 16684 bytes
font_01_sfnt_off00011790.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11790 16792 bytes
font_02_sfnt_off00012fa7.bin
24ff535c004c2157527d1f7b72ea43c33b8ce4197935e58de7d232f5ec64902f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FA7 11004 bytes