Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4b33c18a9327663…

MALICIOUS

PDF

76.1 KB Created: 2020-11-22 23:39:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 3c936be9adbf00f924248041b307a298 SHA-1: de6e8d329943ad5cea30ed65a91059de6f97a620 SHA-256: a4b33c18a93276636948793681229af00b388f2e94316aa2cc43fc8deae58bc5
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. One of the embedded URLs, 'https://traffking.ru/123?utm_term=android+pie+apk', suggests a lure related to Android software. No scripts were extracted, but the PDF structure itself facilitates the distribution of these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://traffking.ru/123?utm_term=android+pie+apk PDF link annotation
    • https://dujezipiver.weebly.com/uploads/1/3/4/6/134610991/7fab4454a2fc2.pdfIn PDF document text
    • https://dudakodut.weebly.com/uploads/1/3/4/4/134497067/xeviwotopiluwes.pdfIn PDF document text
    • https://kusopexel.weebly.com/uploads/1/3/4/5/134526262/b3973d035a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476595/normal_5fb3f0ca3df60.pdfIn PDF document text
    • https://vujerige.weebly.com/uploads/1/3/4/4/134467486/sulujopaxibokip-jezaredipufume-kijigowivomag.pdfIn PDF document text
    • https://vokozigaga.weebly.com/uploads/1/3/4/3/134316184/14317cfa9.pdfIn PDF document text
    • https://bupefozatige.weebly.com/uploads/1/3/4/3/134384552/49cb400a381d37.pdfIn PDF document text
    • https://nafizanoride.weebly.com/uploads/1/3/4/5/134596231/84c31.pdfIn PDF document text
    • https://lifagixuwemup.weebly.com/uploads/1/3/0/9/130969738/kosoviwubifano.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/80619a95-ec64-45d7-bc1d-dc02f410fa6d/39063206929.pdfIn PDF document text
    • https://s3.amazonaws.com/remuv/blocklauncher_0.14.0_apk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f9994547-9679-49fe-b2c9-24cec72d0d77/binovusani.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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bb98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB98 4504 bytes
SHA-256: 0dd72dd9438712202e857d42a901a8fb6e2c20e30acf752d85c45980cd4ffe43
font_01_sfnt_off0000cad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAD4 2532 bytes
SHA-256: 9ceaa032489b49998f6d0c69252ae37e6fbfd03c114d5ca778e2d2ab2774a005
font_02_sfnt_off0000d5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FC 11560 bytes
SHA-256: b0adbf41c4cc615f3732ba281717d82ff7ad4dcd07fc84a7ed3518db57ef19cf
font_03_sfnt_off0000fb92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB92 16896 bytes
SHA-256: d4f1119e1222acc0b8362f1dc779369ba10fdcd159356eaaac6adb880e273fd1
font_04_sfnt_off00011333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11333 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c