Malicious PDF — malware analysis report

Static analysis result for SHA-256 398f2e320238ef48…

MALICIOUS

PDF

82.8 KB Created: 2021-09-21 06:27:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b2a67be7f13a8aaaaacf4371a733f49f SHA-1: 2f77b5a4917d2ddf951d19be9eee669ca3b9e12c SHA-256: 398f2e320238ef4824b42c522a240153fa91bdc7d8d48abd9b4c82bb87d1e2aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many of which point to disposable hosting or compromised CMS upload directories, suggesting a link farm or phishing lure. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this, indicating the PDF is used to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crewmak.ru/uplcv?utm_term=clear+cache+on+this+device
    • http://sovaimm.it/userfiles/files/wudomaxagi.pdf
    • http://marinapogon.pl/upload/file/33857130135.pdf
    • http://xtra360.net/campannas/file/baxesijezipewokogepod.pdf
    • http://improntediteatro.it/userfiles/files/tadaj.pdf
    • http://badgerhillfarm.uk/49663153002.pdf
    • http://www.bargiel.com.pl/ckfinder/userfiles/files/niwojetaworoxovazarenumo.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613394144ac99---zowajefifabifumo.pdf
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/puzanibak.pdf
    • http://bookblog.kr/data/file/files/53205641132.pdf
    • http://lehnerkom.de/images/uploaded/file/92062801207.pdf
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/56713689684.pdf
    • https://agrando.cz/files/file/zizijozigavud.pdf
    • https://xn--b8qxb801j.tw/upload/files/5196879094.pdf
    • http://coinproject.com/userfiles/image/file/89314249440.pdf
    • https://ostrichtours.com/ckfinder/userfiles/files/9411737047.pdf
    • https://acgroupenterprise.com/userfiles/file/75948948295.pdf
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/4v8o1qh8hg1f7o2lkharmgbdcg/90528438043.pdf
    • http://skncn.com/u/files/daxeb.pdf
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/50141898313.pdf
    • http://tc-antey.ru/uploads/files/41121647547.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f946424c20---xigepanifojukixofuwewew.pdf
    • https://mehreganimaging.ir/images/upload/files/loxag.pdf
    • https://hahapediatric.com/uploads/files/202109081428006231.pdf
    • http://checopharma.com/upload/files/50529742406.pdf
    • http://bjyhyy.cn/filespath/files/20210912031720.pdf
    • 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_off0000dfdb.bin
b5ebcda8bf382f18183ad52586d9b080ef56b55da1462985680e7bbddfd2c983
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDB 17732 bytes
font_01_sfnt_off00010d7a.bin
e4183f5bd52070cf34bfd68d25d4965de03037c34cba4350a127005004e437b1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D7A 10564 bytes
font_02_sfnt_off0001258f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1258F 16792 bytes