Malicious PDF — malware analysis report

Static analysis result for SHA-256 f289344a13b52eba…

MALICIOUS

PDF

68.5 KB Created: 2021-09-28 22:23:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 69171147c74851f400e8fa152f3b033f SHA-1: a1d90e5c4127f91d40c028cb20a1ddbe2980913f SHA-256: f289344a13b52eba25f93135ca93293d7930ec8f601b4120de5c03662dd260db
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm pointing to compromised WordPress upload storage and disposable hosting. This indicates a phishing or scamming attempt, likely delivered as a spearphishing attachment. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://catamma.ru/uplcv?utm_term=free+fire+new+update+app+download PDF link annotation
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/zituzuzivaxutaxomad.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132b3f11d588---13553687071.pdfIn PDF document text
    • https://halkum.rs/files/62732192127.pdfIn PDF document text
    • http://sun-marche.com/app/webroot/js/ckfinder/userfiles/files/69190610306.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3b1a0ce66---11575591166.pdfIn PDF document text
    • http://go-pxl.com/uploads/files/92662175767.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210913_0CD028F61D5151AB.pdfIn PDF document text
    • https://tele-video.ru/upload/files/posuvanaxir.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/80571608611.pdfIn PDF document text
    • https://uslugiinzynierskie.com/eurostyl/photos/file/gebebivazulidewediti.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613b61c5e2f78---xevixodusikatorokimad.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/99480197442.pdfIn PDF document text
    • http://yongqingtech.com/d/files/fipomavig.pdfIn PDF document text
    • https://semsaesp.com/ckfinder/userfiles/files/97110628068.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134d13718059---futofavaxekitomol.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/44283427650.pdfIn PDF document text
    • http://amongelite.com/ci/userfiles/files/lidakegajowazomigigod.pdfIn PDF document text
    • http://www.bandungmesin.com/file/tuwiwemasixi.pdfIn PDF document text
    • https://ikima.fr/uploads/file/piseni.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/64355854176.pdfIn PDF document text
    • https://speculatio.in/userfiles/file/nejatimaguki.pdfIn PDF document text
    • http://ticketsperiodico.com/galeria/files/33822899751.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ad35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD35 10488 bytes
SHA-256: 26a52525d05c1b0f3f3db0c5852fec2d6cf91fca22a4b3905f5a650a08ac2496
font_01_sfnt_off0000c529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC529 15708 bytes
SHA-256: bae1497321e9a87882c231470db163f389badf5c0ffa8682782566739118e39a
font_02_sfnt_off0000ecba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1