Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ef5c41ee4cfca06…

MALICIOUS

PDF

84.0 KB Created: 2021-07-02 18:09:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f043c4fbcddffb406eec38572d4d1dfe SHA-1: c564d4f35b75f95e5184c8bb94555f626d2f3072 SHA-256: 1ef5c41ee4cfca063d450566fa91f1dbc202b29197ce1a0c546fad08346129ac
256 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1555 Credentials from Password Stores

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a phishing lure. Specifically, heuristics indicate it's designed to harvest MFA codes or recovery secrets, consistent with credential theft. Although no scripts were extracted, the PDF structure and embedded URLs suggest it's part of a phishing campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 8

  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/lcseqniv7r6h9pmsssnrk7ro41/vivodexexomemokixidujorej.pdf
    • https://dcoderesearch.com/uploads/37302939010.pdf
    • https://armagedonspedycja.pl/files/file/11571547871.pdf
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/b8449d0cd277dea5b8457a85ea63e3b7/winuvotasib.pdf
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f95c6a1b35---41633784656.pdf
    • http://gw73patriots.com/clients/1/1e/1ed986c9d410becccfd9995a8318e329/File/20318571355.pdf
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/1pbaqfkvaiulk2v2h2vfrma0aj/zibiledenozof.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cbe60e63ae---zoxosazaxurole.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/b276d9858f2e410b1cf734fa3ffa1d93/widumuguwitisuxat.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16081432fdf22b---20116778297.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/84be2d779bc99ee1b1aa93a4bec4bb01/26037622031.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160b1d0a56a3ce---2850364264.pdf
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a487b13d2---filawikenabu.pdf
    • http://kopdesign.nl/userfiles/file/sesejijarevawududekad.pdf
    • https://www.tanyadantus.com/wp-content/plugins/super-forms/uploads/php/files/e24d2625e9f54c7cdeb0450ac47a8459/47152604731.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/a3225ff7bb51193f9648945aa15e4f12/68762698468.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ac4d1228a---8148807033.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608f460ab65a0---55962454919.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/0l4jko0vghjvlcf8tqf5jr1791/rilezikuwerelatesebobuwu.pdf
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c74b7858550---17042884366.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d2b9721bb---tonurizixazedeku.pdf
    • http://fenotropil.ru/userfiles/file/vamivigoziwovujira.pdf
    • http://hgbs.de/userfiles/file/4215828561.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=modern+day+cryptography
    • 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_off0000e65b.bin
39dd58030dedae56d1fc7ed4b651d28c30ade4f4cc261103f67a69e853bf189e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE65B 17168 bytes
font_01_sfnt_off00011309.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11309 16792 bytes
font_02_sfnt_off00012b20.bin
a8be2a2f29fa2016ab885d38c652f1489d1ea802bcd64d934b95ec2971adc3a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B20 10592 bytes