Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98ba07dd1c51949…

MALICIOUS

PDF

68.5 KB Created: 2021-05-24 01:06:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 5ad6853350c0fff5362a593da2682893 SHA-1: 19e3892d9d1925d0ef1acfb8f6d912cbdde4eb8a SHA-256: a98ba07dd1c5194944253272f6dd89db911cf17368003926893ad3dc0cbb30d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting it's used to distribute further malicious content. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://veraschwemmle.de/fckdata/file/15013159597.pdf In PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb40a172fe---53372498444.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cca2a8af9e---wopasexosaravubuxutu.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/gunadidedevadad.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile/%5C/bazaludumiwadu.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16072e15ec56a0---nexusikexiwo.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/p45dth15vp1vdoqcoh7h34msra/gozobapulasakosogujere.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb9bf166ba---60324846912.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/dipirakatiforu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a37dda3ac6f---fujajuwevitifegeke.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/zukodoz.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d81a4cfcc7---nojegolakenedasilad.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160986a1a5966f---kilokimusuboduxa.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/pokarijugi.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/7pnss53jtnct9ffctk4fbbiuc3/16596151080.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/4e94e9a49936a852fe5d2e7cf2313641/74580713202.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1f694b8970---dezasobapi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+to+recover+a+groin+strainPDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d229.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD229 5048 bytes
SHA-256: ec7cfe5d4c391368f2d1e52b57c9e7c2f39c3cd8da13aa4f344bc9525670b164
font_01_sfnt_off0000e37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE37E 9888 bytes
SHA-256: 8b0ea2b458a6a6b276f666f29d981796cae9577c0d740ad423e5a122ce4d2916