Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0917c5678a9d0fd…

MALICIOUS

PDF

80.0 KB Created: 2021-09-20 03:15:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 54a56e441be64790901b7bce44564113 SHA-1: 874c39cef37d6ab4e4506719744abdc62fb9ef1d SHA-256: a0917c5678a9d0fd71021802988fca4ed3412abd549fddc297ca80a650522c5b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farm heuristics strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://irlanc.ru/uplcv?utm_term=how+do+i+change+my+voicemail+on+my+android PDF link annotation
    • http://airsoft1.ro/files/file/jarinulowigif.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/sazaderuzip.pdfIn PDF document text
    • http://hiroshima-teishaku.com/userfiles/file/4941915604.pdfIn PDF document text
    • http://centonze-vini.com/userfiles/files/tisemibedugibo.pdfIn PDF document text
    • http://rbtyutj01.com/userfiles/files/zetixixedu.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16130953f6d2f7---runikuvojitesuxom.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/76c9e8e7c8412ddd0004ff27286ee7db/64987545685.pdfIn PDF document text
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/78807307824.pdfIn PDF document text
    • http://xaydunghoangthanh.com/img_duhoc/files/jexapexez.pdfIn PDF document text
    • http://cuacuonbinhduong.com/upload/files/80370868424.pdfIn PDF document text
    • http://www.radio-kum.si/data/files/94820559407.pdfIn PDF document text
    • https://laser123.com/geektic/files/67357720008.pdfIn PDF document text
    • https://n-tlg.com/files/file/46031919820.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/30262715631.pdfIn PDF document text
    • https://breedlife.com/upload/files/zurunomulitijosedazaragiv.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/vaziwukokuvuxobitolivem.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/82787044953.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/nibuk.pdfIn PDF document text
    • https://okazionche.com/files/xiperulaxulokoxixuwumu.pdfIn PDF document text
    • http://integrotech.eu/zdjecia/file/83433570830.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140baba0b159---pipebebitidivumedig.pdfIn PDF document text
    • http://voyagevietnamlaos.com/hinhanh/file/kafowapanaj.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/kudowujurinozujozi.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_off0000d41b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD41B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC32 10808 bytes
SHA-256: de3c062315bc52390464081d3e446f0db52d0156604a70c2e9fa289285f1aea0
font_02_sfnt_off000104a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A5 17908 bytes
SHA-256: b3ec7c782868c0e649169d72a73e29918c4f428b45ac21727e0a7ec51f9b027f