Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4fbb0ddc782d767…

MALICIOUS

PDF

83.6 KB Created: 2021-09-14 08:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7935b86a8fbffdf25709008a7efbc29e SHA-1: 40c7ad58bfc7dd1b0eff6de33bd4a1a700e43fe9 SHA-256: f4fbb0ddc782d76795e1bc7f9f9ad5e01a831bd43d57dac1ab3fe53f87a3f6fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The presence of numerous links with 'utm_term' parameters suggests an attempt to manipulate search engine results or lure users with specific search queries.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://wastran.ru/uplcv?utm_term=puffin+browser+pro+cracked+apk PDF link annotation
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/ir7jlj0nhutmuu5mrafl1t8ib2/54084445996.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/kuvob.pdfIn PDF document text
    • http://gazomotor.com/allinone/file/50887327679.pdfIn PDF document text
    • http://talesma.com/E/file/rapowasuretigixi.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/fulepitigifanaxaj.pdfIn PDF document text
    • http://maulich.vn/attachment/files/kazowabeviri.pdfIn PDF document text
    • http://njchemland.com/upload/files/64051846407.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/17699300292.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/78160048906.pdfIn PDF document text
    • http://hzxf.com/images/upload/File/gejadozaxugefatobidobux.pdfIn PDF document text
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/dujonorinomigonil.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/16272487235.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0d860b701---nefidupuviziwezotamekivaz.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/86298135796.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/2fb8304710e5a849c0e1ce4c5691862e/57117648955.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/zuvekeredufejop.pdfIn PDF document text
    • https://newshieldinsurance.com/demo/gsa/final/images/file/mawinazirifuwusonobewuk.pdfIn PDF document text
    • https://eghamatkade.com/basefile/eghamatkadecom/files/37798517035.pdfIn PDF document text
    • http://xmzs.org/userfiles/file/8422107598.pdfIn PDF document text
    • http://elma1.ru/!upload/files/webuki.pdfIn PDF document text
    • http://language-coach.pl/uploads/files/ralojepulazo.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613376e960129---fipirexoxe.pdfIn PDF document text
    • https://kientrucqhouse.com/uploads/image/files/37436454586.pdfIn PDF document text
    • https://hijaulumut.com/contents/files/15497969935.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_off0000e0bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D4 10888 bytes
SHA-256: 6591dbf4ed3b689d996892632143cf51e9194f80531e89a9c91d34283702fad0
font_02_sfnt_off000111f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F3 18180 bytes
SHA-256: d94da9e59f95c6ca485bec4ea376d05dfeaea1d08a23de6912542a8e75e16524